JP2001133128A - Refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a refrigerator employing combustible refrigerant in which the risk of firing is reduced when defrost operation is performed under an environment where the combustible refrigerant has leaked. SOLUTION: Since a refrigeration cycle using combustible refrigerant comprises juxtaposed coolers 23, 24 for refrigeration compartment and freezing compartment, temperature of a defrost means for the freezing compartment cooler 24 can be lowered and possibility of firing the combustible refrigerant can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a refrigerator.

[0002]

2. Description of the Related Art In recent years, a refrigerator disclosed in Japanese Patent Application Laid-Open No. 8-54172 has been known as a refrigerator having improved defrosting efficiency.

Hereinafter, the conventional refrigerator will be described with reference to the drawings.

FIG. 27 is a longitudinal sectional view of a main part of a conventional refrigerator.

In FIG. 27, 1 is a refrigerator main body, 2 is a freezing room inside the refrigerator main body 1, 3 is a refrigerator room inside the refrigerator main body 1, 4 is a freezing room door, 5 is a refrigerator room door, and 6 is a refrigerator room door. A partition wall separating the freezer compartment 2 and the refrigerator compartment 3, a freezer compartment suction port 7 for sucking air in the freezer compartment 2, a refrigerator compartment suction port 8 for sucking air in the refrigerator compartment 3, and a discharge port 9 for discharging cool air. Reference numeral 10 denotes an evaporator, and 11 denotes a fan for circulating cool air.

Reference numeral 12 denotes an evaporator partition wall for separating the evaporator 10 and the freezing compartment 2, 13 denotes a trough, 14 denotes a drain port, 15 denotes a defrosting tube heater in which a coiled nichrome wire is covered with a glass tube, Reference numeral 16 denotes a roof for preventing evaporation noise generated when defrost water directly drops on and contacts the defrost tube heater 15;
Reference numeral 7 denotes a metal bottom plate provided between the tub 13 and the defrosting tube heater 15 and insulated and held.

Next, the operation will be described. When cooling the freezer compartment 2 or the refrigerator compartment 3, the refrigerant flows through the evaporator 10 to cool the evaporator 10. Fan 11 in the same way
, The heated air of the freezing room 2 or the refrigerated room 3 is sent from the freezing room suction port 7 or the refrigerated room suction port 8 to the cooling chamber 20, and the heat is exchanged by the evaporator 10 to be cooled and cooled from the discharge port 9. The wind is sent into the freezer compartment 2, and cool air is sent from the freezer compartment 2 to the refrigerator compartment through a communication port (not shown).

Here, the air that exchanges heat with the evaporator 10 is:
Since the air is humidified by the inflow of high-temperature outside air due to the opening and closing of the freezer compartment door 4 and the refrigerating compartment door 5 and the evaporation of the moisture of the preserved food in the freezer compartment 2 and the refrigerating compartment 3, the temperature is lower than the air. Moisture in the air becomes frost and forms frost on the evaporator 10,
As the amount of frost increases, the heat transfer between the surface of the evaporator 10 and the air that exchanges heat is hindered, and the air flow decreases due to airflow resistance.

Therefore, before the cooling becomes insufficient, the nichrome wire of the defrosting tube heater 15 is energized. When energization of the nichrome wire is started, heat rays are radiated from the nichrome wire to the evaporator 10 and peripheral components. At this time, a part of the heat ray radiated to the bottom plate 17 is reflected by the heater wire from the shape of the bottom plate 17, and the other part is reflected toward the evaporator 10 and other peripheral parts.

Thus, the evaporator 10, the tub 13, the drain 1
The frost that has arrived near 4 is melted in water. A part of the defrosted water thus melted falls directly into the tub 13, and the others fall into the tub 13 by the roof 16, avoiding the defrosting tube heater 15, and are drained from the drainage port 14 to the outside of the refrigerator. You.

[0011]

However, in the above-mentioned conventional construction, the temperature of the glass surface is, of course, very high, not to mention the surface of the nichrome wire of the defrosting tube heater 15, and the bottom plate 17 is provided with a tube. A portion of the heat rays radiated from the tube heater 15 near the heater 15
, The temperature of the tube heater 15 rises abnormally. The heating value of the tube heater 15 is the same as that of the tube heater 1.
5 is the sum of the amount of heat used to raise the temperature and the amount of heat radiated to the outside. Therefore, an increase in the temperature of the tube heater 15 means a decrease in the amount of heat radiated to the outside. Since the defrosting of the evaporator 10 and its peripheral parts is performed, the amount of heat used for defrosting the evaporator 10 and its peripheral parts is reduced, the defrosting time is extended, and as a result, the heat generation time of the tube heater 15 is reduced. Prolonged to increase power. From this, the power is increased, and when the flammable refrigerant is used as the refrigerant and the flammable refrigerant leaks from a pipe installed in a portion communicating with the evaporator 10 or the inside of the refrigerator, a defrosting pipe heater is used. There is a problem that the risk of ignition by reaching the ignition temperature by the energization of No. 15 becomes extremely high.

SUMMARY OF THE INVENTION In view of the above problems, the present invention aims at saving energy of a refrigerator by reducing electric power used for defrosting, and in an environment where used and combustible refrigerant leaks into an installation atmosphere of a defrosting means. An object of the present invention is to provide a refrigerator that can safely use a flammable refrigerant because the possibility of ignition of the flammable refrigerant can be reduced even when defrosting is performed.

[0013]

In order to achieve the above object, a refrigerator according to the present invention has a refrigerator main body in which a freezer compartment and a refrigerator compartment are completely independent, and a high evaporation temperature for a compressor, a condenser and refrigeration. Refrigerator compartment cooler, high evaporation temperature decompression mechanism with low decompression for high evaporation temperature, freezer compartment low temperature refrigeration compartment cooler connected in parallel with the refrigerator compartment cooler, low evaporation temperature A pressure-reducing mechanism for a large evaporation pressure for low evaporation temperature, a switching valve for controlling the refrigerant not to flow simultaneously to the refrigerator cooler and the freezer cooler, and a refrigerant at the outlet of the freezer cooler. The refrigerating cycle includes a refrigeration cycle operatively connected to a check valve for preventing backflow, and defrosting means for defrosting the freezer compartment cooler.

A refrigeration cycle in which a compressor, a condenser, a decompression mechanism, and an evaporator are connected; and a defrosting means for defrosting the flammable refrigerant at a temperature lower than an ignition temperature of a flammable refrigerant for defrosting the evaporator. The cycle uses a flammable refrigerant.

[0015] From this, since there are two coolers as compared with one conventional cooler, the amount of frost formed in the cooler for the freezer compartment is reduced, and gasification occurs due to the heat generated by the defrost to cool the cooler for the freezer compartment. Excess refrigerant vapor flowing out of the refrigerator does not flow back to the freezer compartment cooler by the check valve, and the refrigerant flowing backward need not be heated.

As described above, when the refrigerator for the freezer compartment is defrosted, the amount of frost to be defrosted by the defrosting means is reduced,
Since it is not necessary to heat the useless refrigerant, the power consumption of the defrosting means can be reduced as compared with the conventional method, thereby saving energy and reducing the calorific value of the defrosting means to a heat value lower than the ignition temperature of the flammable refrigerant. Therefore, even if defrosting is performed in an environment where the flammable refrigerant has leaked into the installation atmosphere of the defrosting means while maintaining the defrosting ability at or above the conventional level, the danger due to ignition of the flammable refrigerant can be reduced. .

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention provides a refrigerator body in which a freezer compartment and a refrigerator compartment are completely independent,
A compressor, a condenser, a refrigerator for a refrigerator having a high evaporation temperature for refrigeration, a decompression mechanism for a high evaporation temperature having a small reduced pressure for the high evaporation temperature, and a refrigeration system connected in parallel with the refrigerator for the refrigerator. Refrigerator compartment cooler with low evaporation temperature, low evaporation temperature decompression mechanism with large decompression for low evaporation temperature, so that refrigerant does not flow simultaneously to the refrigerator compartment cooler and the freezer compartment cooler. The system includes a refrigeration cycle in which a switching valve to be controlled, a check valve for preventing backflow of refrigerant at the outlet of the freezer compartment cooler are functionally connected, and defrosting means for defrosting the freezer compartment cooler. In the freezer compartment cooler, only the moisture of the air in the freezer compartment is frosted, and the amount of frost is smaller than that of a conventional cooler that cools all the rooms such as the refrigerator compartment and the freezer compartment. At the same time, the excess refrigerant vapor that has been gasified by the heat generated by defrost and has flowed out of the freezer cooler is Not flow back into the freezer compartment cooler outside the stop valve, the refrigerant amount of the refrigerating compartment the cooler during defrost is reduced.

From the above, when defrosting the freezer compartment cooler, the power consumption of the defrosting means can be reduced by reducing the amount of frost and the amount of heating of the refrigerant in the freezer compartment cooler, thereby saving energy. Since the defrosting means can reduce the calorific value to a value lower than the ignition temperature of the flammable refrigerant, the defrosting can be performed in an environment where the flammable refrigerant leaks to the installation atmosphere of the defrosting means while maintaining the same defrosting ability as before. Even when it is performed, the danger due to the ignition of the combustible refrigerant can be reduced.

According to the second aspect of the present invention, when the defrosting of the freezer compartment cooler is performed, the switching valve is controlled so that the refrigerant does not flow into the freezer compartment cooler. Only the moisture of the air in the freezing room is frosted, and the amount of frost is reduced with respect to the cooler that cools all the rooms such as the refrigerator room and the freezing room with one conventional cooler, and the heat generated by the defrost is generated. Excess refrigerant vapor that is gasified and flows out of the freezer compartment cooler does not flow back to the freezer compartment cooler by the check valve.

Further, since the high-pressure refrigerant does not flow into the freezer compartment cooler by controlling the switching valve, the amount of refrigerant in the freezer compartment cooler during defrosting is reduced.

From this, it is possible to further reduce the consumption time of the defrosting means by reducing the amount of frost and further reducing the amount of heating of the refrigerant, thereby saving energy. Reduces the risk of ignition of flammable refrigerant even when defrosting is performed in an environment where flammable refrigerant has leaked into the installation atmosphere of the defrost means while maintaining the same defrosting capacity as before it can.

Further, in the invention according to claim 3, when the defrosting of the freezer compartment cooler is performed, the switching valve is controlled so that the refrigerant does not flow into both the refrigerator compartment cooler and the freezer compartment cooler. Since the defrosting means is operated after the compressor is operated for an arbitrary time above, only the moisture of the air in the freezing room is frosted in the freezing room cooler. The amount of frost on the cooler that cools all the rooms, such as the room, is reduced, and the excess refrigerant vapor that has been gasified by the heat generated by defrost and that has flowed out of the cooler for the freezer is returned to the freezer by the check valve. There is no backflow to the cooler, and the high-pressure refrigerant does not flow into the freezer cooler due to the control of the switching valve.

Further, by operating the compressor with the switching valve closed immediately before defrosting, the amount of refrigerant in the refrigerator freezer becomes extremely small.

From this, it is possible to further reduce the consumption time of the defrosting means by reducing the amount of frost and further reducing the amount of the refrigerant heated in the freezer cooler, thereby saving energy. Since the amount of heat generated can be reduced to below the ignition temperature and there is almost no refrigerant in the freezer compartment cooler when the freezer compartment cooler is heated during defrosting, flammable refrigerants maintain the same defrosting capacity as before However, even when defrosting is performed in an environment where the air leaks into the installation atmosphere of the defrosting means, the danger due to ignition of the combustible refrigerant can be reduced.

According to the present invention, when the defrosting of the freezer compartment cooler is performed, the switching valve is controlled so that the refrigerant does not flow into both the refrigerator compartment cooler and the freezer compartment cooler. Since the defrosting means is operated after the compressor is operated for 20 to 90 seconds on the above, only the moisture of the air in the freezing room is frosted in the freezing room cooler, and the cooling room or the freezing room is cooled by one conventional cooler. The amount of frost on the cooler that cools all the rooms such as the freezing room is reduced, and the excess refrigerant vapor that is gasified by the heat generated by defrost and flows out from the freezer cooler is returned to the freezing room by the check valve. There is no backflow to the refrigerator cooler, and the high pressure refrigerant does not flow into the refrigerator cooler due to the control of the switching valve.

Further, by operating the compressor with the switching valve closed immediately before defrosting, the amount of refrigerant in the refrigerator freezer becomes extremely small.

From this, it is possible to further reduce the consumption time of the defrosting means by reducing the amount of frost and further reducing the amount of refrigerant heated in the freezer cooler, thereby saving energy. The amount of heat generated can be reduced to below the ignition temperature, and there is almost no refrigerant in the freezer compartment cooler when the freezer compartment cooler is heated during defrosting. Even when defrosting is performed in an environment in which the refrigerant leaks into the installation atmosphere of the defrosting means, the risk of ignition of the flammable refrigerant can be reduced.

In addition, the operation time of the compressor is reduced from 20 seconds to 9 hours.
By setting the time to 0 second, an extremely low pressure is prevented from dropping extremely, and the compressor has reliability.

According to the fifth aspect of the present invention, the switching valve is opened so that the refrigerant flows to the freezer compartment cooler before the defrosting means is stopped. Only the moisture of the air is frosted, and the amount of frost is reduced with respect to the cooler that cools all the rooms such as the refrigerator compartment and the freezer compartment with one conventional cooler, and gasified by the heat generated by the defrost. Excess refrigerant vapor flowing out of the freezer compartment cooler does not flow back to the freezer compartment cooler by the check valve, and the high-pressure refrigerant does not flow into the freezer compartment cooler by controlling the switching valve.

Further, by operating the compressor with the switching valve closed immediately before defrosting, the amount of refrigerant in the refrigerator freezer becomes extremely small.

From this, it is possible to further reduce the consumption time of the defrosting means by reducing the amount of frost and further reducing the amount of refrigerant heated in the freezer cooler, thereby saving energy. Since the calorific value can be reduced to a value lower than the ignition temperature, the flammable refrigerant can be reduced even when defrosting is performed in an environment where the flammable refrigerant leaks to the installation atmosphere of the defrosting means while maintaining the same defrosting capacity as before. The danger due to the ignition of fire can be reduced.

In addition, since the difference between the high pressure and the low pressure becomes small when the compressor is started after defrosting is completed, the compressor starts smoothly, and the freezing room which has been heated by defrosting is cooled smoothly. Therefore, it is possible to prevent deterioration of the stored food in the freezer due to the temperature rise in the refrigerator during defrosting.

In the invention according to claim 6, the switching valve is opened so that the condenser and the refrigerator cooler communicate with each other during the operation of the defrosting means. Only the moisture in the air is frosted, and the amount of frost on the cooler that cools all the rooms, such as the refrigerator compartment and the freezer compartment, is reduced by one conventional cooler, and gasification is caused by the heat generated by defrosting. Excess refrigerant vapor flowing out of the freezer compartment cooler does not flow back to the freezer compartment cooler by the check valve, and the high-pressure refrigerant does not flow into the freezer compartment cooler by controlling the switching valve.

Further, by operating the compressor with the switching valve closed immediately before defrosting, the amount of refrigerant in the refrigerator freezer becomes extremely small.

From this, it is possible to further reduce the consumption time of the defrosting means by reducing the amount of frost and further reducing the amount of the refrigerant heated in the freezer cooler, thereby saving energy. The amount of heat generated can be reduced to below the ignition temperature.There is almost no refrigerant in the freezer compartment cooler when the freezer compartment cooler is heated during defrosting. However, even when defrosting is performed in an environment where the air leaks into the installation atmosphere of the defrosting means, the danger due to ignition of the combustible refrigerant can be reduced.

Further, during defrosting, the switching valve is controlled so that the low-pressure refrigerator cooler and the high-pressure condenser communicate with each other, and the differential pressure between high and low pressures before and after the compressor is small.
When cooling the freezing compartment after the completion of defrosting, the compressor started to operate smoothly only by switching the switching valve so that the refrigerant flows through the freezing compartment cooler. The freezing compartment can be cooled smoothly, and deterioration of the stored food in the freezing compartment due to the temperature rise in the refrigerator after defrosting can be prevented.

According to the seventh aspect of the present invention, since the compressor is operated during the operation of the defrosting means, only the air in the freezing compartment is defrosted by the freezing compartment cooler. The amount of frost formed on the cooler that cools all the rooms such as the refrigerator compartment and the freezer compartment by one becomes small, and the excess refrigerant vapor gasified by the heat generated by the defrost and flowed out from the cooler for the freezer compartment is removed. There is no backflow to the freezer compartment cooler due to the check valve, and the high pressure refrigerant does not flow into the freezer compartment cooler by controlling the switching valve.

Further, by operating the compressor with the switching valve closed immediately before defrosting, the amount of refrigerant in the refrigerator freezer becomes extremely small.

From this, it is possible to further reduce the consumption time of the defrosting means by reducing the amount of frost and further reducing the amount of heating of the refrigerant in the freezer cooler, thereby saving energy. The amount of heat generated can be reduced to below the ignition temperature.There is almost no refrigerant in the freezer compartment cooler when the freezer compartment cooler is heated during defrosting. However, even when defrosting is performed in an environment where the air leaks into the installation atmosphere of the defrosting means, the danger due to ignition of the combustible refrigerant can be reduced.

Further, in addition to being able to cool the refrigerating compartment during the defrosting of the freezing compartment cooler, when the freezing compartment is cooled after the completion of the defrosting, a switching valve is used to flow the refrigerant to the freezing compartment cooler. Cooling can be started smoothly just by switching to freezing, so that the freezing compartment can prevent the deterioration of stored foods due to the temperature rise in the compartment after defrosting, It is possible to prevent food deterioration caused by temperature rise due to invasion of outside air due to the stop of the compressor during defrost.

The invention according to claim 8 provides a refrigeration cycle in which a compressor, a condenser, a pressure reducing mechanism, and an evaporator are connected, wherein the temperature is lower than the ignition temperature of a flammable refrigerant for defrosting the evaporator. Since a flammable refrigerant is used in the refrigeration cycle, the flammable refrigerant heated together with the evaporator during the defrosting of the evaporator has a higher thermal conductivity than the conventional HCF refrigerant. In addition, the calorific value of the defrosting means can be reduced.

From this, even if defrosting is performed in an environment where the flammable refrigerant has leaked into the installation atmosphere of the defrosting means while maintaining the same defrosting ability as in the past, there is a danger due to the ignition of the flammable refrigerant. Can be reduced.

According to a ninth aspect of the present invention, the defrosting means is provided in the first glass tube and the first glass tube has an outer diameter smaller than an inner diameter of the first glass tube. 2 and a heater wire made of a metal resistor disposed between the first glass tube and the second glass tube. As the contact area between the high-temperature gas and the glass tube increases and the contact area between the outside air and the glass tube increases, the heat radiation from the heater wire to the outside air is promoted, the heater wire temperature decreases, and the defrost means Does not reach the temperature until the combustible refrigerant ignites.

Furthermore, even if the flammable refrigerant leaks in the event that the heater wire rises above the ignition temperature of the flammable refrigerant for some reason, the heater wire is surrounded by the first glass tube and the second glass tube. Since the volume around the heater wire is small, the amount of combustible refrigerant flowing into the vicinity of the heater wire inside the glass tube of the combustible refrigerant is small, and the amount of air containing oxygen necessary for the combustible refrigerant to burn is reduced. It does not ignite because it is small.

From this, even if defrosting is performed in an environment where the flammable refrigerant has leaked into the installation atmosphere of the defrosting means while maintaining the same defrosting ability as before, there is a danger due to the ignition of the flammable refrigerant. Can be extremely reduced.

According to a tenth aspect of the present invention, the defrosting means is provided with a glass tube, and a heater wire made of a metal resistor is installed inside the glass tube and filled with glass beads. In the heat generation of the heater wire at the time, since the glass beads have a very good thermal conductivity to the air, heat conduction from the heater wire to the glass tube is promoted, and heat transfer from the heater wire to the outside air through the glass tube. Accelerated, the surface temperature of the heater wire decreases, and the heater wire does not reach the temperature before the combustible refrigerant ignites.

Further, even if the heater wire rises above the ignition temperature of the flammable refrigerant for some reason, even if the flammable refrigerant leaks, since the space in the glass tube is smaller, the flammable refrigerant glass The risk of ignition is lower because the amount of flammable refrigerant flowing around the heater wire inside the pipe is smaller and the amount of air containing oxygen required for flammable refrigerant to burn is also smaller. I do.

From this, even if defrosting is performed in an environment where the flammable refrigerant leaks into the installation atmosphere of the defrosting means while maintaining the same defrosting ability as before, there is a danger due to the ignition of the flammable refrigerant. Can be extremely reduced.

Further, according to the present invention, since the glass beads are transparent, the heat generation of the heater wire during defrosting is very good because the glass beads have a very good thermal conductivity to air. Heat transfer from the wire to the outside air through the glass tube is promoted, and the surface temperature of the heater wire decreases.

In addition, since the glass beads are transparent,
The radiant heat rays generated by the heating of the heater wires are transmitted, and the temperature rise of the glass beads due to the absorption of the radiant heat rays can be reduced, so that the temperature of the glass beads decreases. And the heater wire does not reach the ignition temperature of the flammable refrigerant.

If the heater wire rises above the ignition temperature of the flammable refrigerant for some reason, even if the flammable refrigerant leaks, since the space in the glass tube is smaller, the flammable refrigerant glass Since the amount of combustible refrigerant flowing around the heater wire inside the pipe is smaller and the amount of air containing oxygen necessary for the combustible refrigerant to burn is also smaller, the danger of ignition is greater. descend.

From this, even if defrosting is performed in an environment where the flammable refrigerant has leaked into the installation atmosphere of the defrosting means while maintaining the same defrosting ability as in the past, there is a danger due to the ignition of the flammable refrigerant. Can be extremely reduced.

Further, according to the twelfth aspect, the glass beads filled in the glass tube have a filling amount of 100%.
Therefore, in the heat generation of the heater wire during defrosting, since the glass beads have a very good thermal conductivity to air, heat transfer from the heater wire to the outside air through the glass tube is promoted, The surface temperature drops and does not reach the ignition temperature of the flammable refrigerant.

If the heater wire rises above the ignition temperature of the flammable refrigerant for some reason, even if the flammable refrigerant leaks, since the space in the glass tube is smaller, the flammable refrigerant glass Since the amount of combustible refrigerant flowing around the heater wire inside the pipe is smaller and the amount of air containing oxygen necessary for the combustible refrigerant to burn is also smaller, the danger of ignition is greater. It drops and does not reach the ignition temperature of the flammable refrigerant.

From this, even if defrosting is performed in an environment where the flammable refrigerant has leaked into the installation atmosphere of the defrosting means while maintaining the same defrosting ability as before, there is a danger due to the ignition of the flammable refrigerant. Can be extremely reduced.

Further, the filling rate of the glass beads is set to 100%.
By reducing the stress of the heater wire due to the suppression of thermal expansion by increasing the volume of the space inside the glass tube and absorbing the thermal expansion of the heater wire during heat generation, the life of the heater wire is prolonged and eliminated. The reliability of the frost means can be improved.

According to the thirteenth aspect of the present invention, since both ends of the glass tube are sealed, the heat conductivity of the glass beads is very good with respect to air when the heater wire generates heat during defrosting. Therefore, heat transfer from the heater wire to the outside air through the glass tube is promoted, the surface temperature of the heater wire decreases, and the heater wire does not reach the ignition temperature of the combustible refrigerant.

If the heater wire rises above the ignition temperature of the flammable refrigerant for some reason, even if the flammable refrigerant leaks, since the space in the glass tube is smaller, the flammable refrigerant glass Since the amount of combustible refrigerant flowing around the heater wire inside the pipe is smaller and the amount of air containing oxygen necessary for the combustible refrigerant to burn is also smaller, the danger of ignition is greater. descend.

From this, even if defrosting is performed in an environment where the flammable refrigerant has leaked into the installation atmosphere of the defrosting means while maintaining the same defrosting ability as before, there is a danger due to the ignition of the flammable refrigerant. Can be extremely reduced.

Further, since the glass tube is sealed at both ends, the temperature of the heater wire can be prevented from rising due to the increase of the air layer having poor thermal conductivity in the glass tube due to the outflow of the glass beads. In addition, it is possible to prevent the heater wire from being corroded and broken by moisture contained in the outside air when the outside air flows into the glass tube.

Further, in the invention according to claim 14, since the defrosting means cooling fan for cooling the defrosting means is installed in the vicinity of the defrosting means, the temperature of the surface of the defrosting means decreases, and the heater wire becomes inflammable. The defrosting of the evaporator is promoted by the stirring of the air near the defrosting means while the ignition temperature of the volatile refrigerant is not reached.

From this, even if defrosting is performed in an environment where the flammable refrigerant leaks into the installation atmosphere of the defrosting means while maintaining the same defrosting ability as in the past, there is a danger due to the ignition of the flammable refrigerant. Can be reduced.

According to a fifteenth aspect of the present invention, the defrosting means comprises a glass tube and a heater wire made of a metal resistor inside the glass tube, and radiates radiation to the surface of the glass tube. Since the radiation promoting material is coated, the heat transmitted from the heater wire to the glass tube can be radiated well to the outside air, so the temperature of the glass tube decreases, so the heater wire temperature decreases. Ignition temperature is not reached.

From this, even if defrosting is performed in an environment where the flammable refrigerant leaks into the installation atmosphere of the defrost means while maintaining the same defrosting ability as in the past, there is a danger due to ignition of the flammable refrigerant. Can be reduced.

In the invention according to claim 16, since the radiation promoting material is transparent, the glass tube transmits most of the radiant heat rays from the heater wire and absorbs the remaining part. Since the heat transmitted from the heater wire by the absorbed heat and conduction can be partially radiated to the outside air, the heat transmitted by the absorbed heat and conduction can be satisfactorily radiated to the outside air. The heater wire does not reach the ignition temperature of the combustible refrigerant.

From this, even if defrosting is performed in an environment where the flammable refrigerant has leaked into the installation atmosphere of the defrosting means while maintaining the same defrosting ability as in the past, there is a danger due to the ignition of the flammable refrigerant. Can be reduced.

According to a seventeenth aspect of the present invention, the defrosting means comprises a heating element and a roof for preventing direct contact of the surface of the heating element with defrost water. Since the width of the roof is smaller than the width of the evaporator, the air heated by the heating element convects upward along the roof and performs defrosting in the evaporator.

At this time, since the width of the evaporator is larger than the width of the roof, the high-temperature air leaking from the roof smoothly reaches the evaporator, so that the defrosting ability is improved. Can reduce the calorific value of the defrosting means, can lower the temperature of the defrosting means, and the surface temperature of the defrosting means does not reach the ignition temperature of the combustible refrigerant.

From this, it is possible to save energy and at the same time maintain the same defrosting ability as in the past, while maintaining the same defrosting ability even when the defrosting is performed in an environment where the flammable refrigerant leaks into the installation atmosphere of the defrosting means. The danger caused by ignition of the refrigerant can be reduced.

Further, in the invention according to claim 18, the defrosting means insulates the metal pipe, a heater wire made of a metal resistor installed inside the metal pipe, and the heater wire and the metal pipe. The heat transfer from the defrosting means to the evaporator is performed because the water pan with heating means with heating means is installed below the evaporator. Is good and the defrosting ability is improved, so that if the same defrosting ability is maintained as before, the calorific value of the defrosting means can be reduced, and the surface temperature of the defrosting means can be lowered. The means do not reach the ignition temperature of the flammable refrigerant.

Further, since the water receiving pan with heating means is heated, it is possible to smoothly discharge the defrosted water falling around the evaporator and the evaporator to the outside. With the increase, it is possible to prevent the ventilation resistance of the evaporator from increasing and insufficient cooling.

From this, it is possible to save energy and at the same time maintain the same defrosting ability as in the past, while maintaining the same defrosting ability even when the defrosting is performed in an environment where the flammable refrigerant leaks into the installation atmosphere of the defrosting means. In addition to reducing the risk of ignition of the refrigerant, it is possible to prevent food deterioration due to insufficient cooling after defrosting.

According to a nineteenth aspect of the present invention, the defrosting means comprises a glass tube and a heater wire made of a metal resistor inside the glass tube, and an auxiliary device is provided above the evaporator. Since the heater is installed, not only can the amount of heat generated by the defrosting means be reduced, but also
Since the defrosting ability is improved by simultaneously performing heat defrosting from the direction, it is possible to further reduce the calorific value of the defrosting means,
The defrosting means and the auxiliary heater can lower the temperature below the ignition temperature of the combustible refrigerant.

From this, it is possible to save energy and at the same time to maintain the same defrosting ability as in the past, while maintaining the same defrosting ability even when the defrosting is performed in an environment where the flammable refrigerant leaks into the installation atmosphere of the defrosting means. In addition to reducing the risk of ignition of the refrigerant, it is possible to prevent food deterioration due to insufficient cooling after defrosting.

The twentieth aspect of the present invention provides a refrigeration cycle in which a compressor, a condenser, a decompression mechanism, and an evaporator are functionally connected in an annular manner, and a separate pipe for the refrigeration cycle. It has a bypass pipe that directly pipes the evaporator and the evaporator, and has a valve in the path of the bypass pipe. Since the refrigerant contains a flammable refrigerant, the hot gas refrigerant is opened by opening the valve of the bypass pipe. Is passed through the evaporator for defrosting, so that there is no need for a defrost heater that is higher than the ignition temperature of the flammable refrigerant, and there is an effect that defrost can be performed at a low temperature lower than the ignition temperature of the flammable refrigerant.

According to a twenty-first aspect of the present invention, the valve has an opening / closing function, and since the diameter of the flow path when the valve is open is equal to or larger than the inner diameter of the discharge pipe, the valve of the bypass pipe is opened. When degassing by flowing hot gas to the evaporator,
The hot gas refrigerant flows to the evaporator without receiving resistance from the valve when passing through the valve, and since there is no decrease in the circulation amount of the hot gas refrigerant to the evaporator, the defrost becomes higher than the ignition temperature of the flammable refrigerant. A heater is not required, and defrosting can be performed at a temperature lower than the ignition temperature of the flammable refrigerant, and the defrosting time can be shortened by smoothly flowing the hot gas refrigerant to the evaporator, thereby circulating the hot gas refrigerant. This has the effect of reducing the operating time of the compressor used.

According to a twenty-second aspect of the present invention, the evaporator inlet pipe, which is a pipe from the bypass pipe to the evaporator, is located near the upstream side of the ventilation air for heat exchange, and the suction of the compressor from the evaporator is performed. Evaporator outlet pipe is located near the downstream side of the ventilation air that exchanges heat with the evaporator, so that hot gas refrigerant with a high temperature flows in from the piping located upstream of the ventilation air with a large amount of frost. Defrosting can be performed efficiently, without the need for a defrost heater that is higher than the ignition temperature of the flammable refrigerant, and can be performed at a low temperature lower than the ignition temperature of the flammable refrigerant, and efficiently perform defrosting Thus, the defrosting time can be reduced, and the operation time of the compressor used for circulating the hot gas refrigerant can be shortened.

Further, since the invention according to claim 23 is provided with a water tray with heating means provided with a heating means and a drain port for draining defrost water to the outside of the refrigerator, it is possible to perform defrosting with hot gas refrigerant. The unfrosted frost that has fallen into the water pan with heating means below the evaporator together with the defrost water can be completely melted and turned into water, and the defrost water can be smoothly discharged from the drain port to the outside.
This eliminates the need for a defrost heater that is higher than the ignition temperature of the flammable refrigerant, and enables defrosting at a low temperature lower than the ignition temperature of the flammable refrigerant, and defrost water remains in the water pan with heating means. In this case, it is possible to prevent an insufficient cooling due to an increase in load due to cooling after defrosting and an obstruction of an air passage due to freezing.

Further, in the invention according to claim 24, since the evaporator outlet pipe from the evaporator to the compressor is provided with a heating means, the hot gas refrigerant is condensed in the evaporator by defrost to become a liquid refrigerant and compressed. It can be prevented from flowing into the machine by heating the suction pipe, eliminating the need for a defrost heater that is higher than the ignition temperature of the flammable refrigerant, enabling defrosting at a low temperature lower than the ignition temperature of the flammable refrigerant, and defrosting. Liquid back to the compressor at the time can be prevented.

Further, in the invention according to claim 25, since the valve has a throttling function, defrosting when the amount of frost formed on the evaporator is large, such as at a high outside temperature, is achieved by fully opening and opening the valve. The hot gas refrigerant is circulated to the evaporator for defrosting, and when the amount of frost on the evaporator is small, such as when the ambient temperature is low, the valve is squeezed to reduce the flow rate of the hot gas refrigerant to the evaporator. Defrosting eliminates the need for a defrost heater that is higher than the ignition temperature of the flammable refrigerant, allows defrosting at a low temperature lower than the ignition temperature of the flammable refrigerant, and optimizes defrost according to the amount of defrost. And liquid back to the compressor can be prevented.

According to the twenty-sixth aspect of the present invention, the evaporator outlet temperature detecting means for detecting the temperature is provided at the outlet pipe of the evaporator, and the throttle of the valve is controlled by the evaporator outlet temperature detecting means. Since the state of the refrigerant sucked into the compressor can be kept constant, a defrost heater that is higher than the ignition temperature of the flammable refrigerant is not required. It is possible to prevent breakage due to liquid backing to the liquid and prevent the specific volume from increasing due to the high-temperature gas refrigerant, thereby reducing the circulation amount and reducing the defrosting ability.

In the invention according to claim 27, since the rotation speed of the compressor can be changed, the rotation speed of the compressor is changed according to the defrosting amount when the refrigerant flows through the bypass pipe. Since the flow rate of hot gas can be optimally controlled by this, it is controlled to the minimum rotation speed, so there is no need for a defrost heater that is higher than the ignition temperature of the flammable refrigerant, and at a low temperature less than the ignition temperature of the flammable refrigerant. In addition to being able to defrost and preventing damage due to liquid back to the compressor, it is also possible to perform optimal defrost according to the amount of defrost, thus wasting electricity by operating the compressor more than necessary. There is no need to save energy.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. The same components as those in the related art are denoted by the same reference numerals, and detailed description is omitted.

(Embodiment 1) Embodiment 1 according to the present invention will be described with reference to the drawings.

FIG. 1 is a refrigeration system diagram of a refrigerator according to the first embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of a main part of the refrigerator according to the first embodiment of the present invention.

As shown in FIGS. 1 and 2, reference numeral 18 denotes a compressor,
19 is a condenser, 20 is a switching valve for switching the flow path of the refrigerant,
21 is a low evaporating temperature decompression mechanism with a large decompression amount for the low evaporating temperature, 22 is a high evaporating temperature decompression mechanism with a small decompression amount for the high evaporation temperature, and 23 is a refrigerator compartment cooling with a high evaporating temperature for refrigerating. , 24 is a refrigerator for a freezing room having a low evaporation temperature for freezing, and 25 is a check valve for preventing a backflow of refrigerant from the compressor 18 or the refrigerator 23 for the refrigerator to the refrigerator 24 for the freezing room. .

26 is a defrosting means for defrosting the freezer compartment cooler, 27 is a freezer compartment partition wall separating the freezer compartment and the freezer compartment cooler, and 28 is the freezer compartment air. Freezer fan for ventilating and circulating air through the cooler 24,
Reference numeral 9 denotes a freezer compartment outlet for discharging air cooled by heat exchange in the freezer compartment cooler 24 to the freezer compartment 2, and reference numeral 30 denotes a refrigerator compartment cooler partition wall that separates the refrigerator compartment 3 and the refrigerator compartment cooler 23. , 3
Reference numeral 1 denotes a refrigerator compartment fan for allowing the air in the refrigerator compartment 3 to ventilate and circulate through the refrigerator compartment cooler 23, and 32 discharges air cooled by the heat exchange in the refrigerator compartment cooler 23 to the refrigerator compartment 3. The refrigerating compartment discharge port 33 is an evaporating dish for storing defrost water when the freezer compartment cooler 24 is defrosted by the defrosting means 26.

The refrigerator configured as described above
The operation will be described below.

When the refrigerating compartment 3 is cooled, when the refrigerating compartment 3 reaches a certain set temperature or higher, the compressor 18 is operated by a temperature detecting means (not shown) and circulation of a combustible refrigerant (not shown) in the refrigerating cycle starts. The combustible refrigerant is supplied to the condenser 19
The refrigerant is condensed by heat exchange with the outside air, passes through the high evaporating temperature decompression mechanism 22 by the switching valve 20, flows to the refrigerator cooler 23, and is sucked into the compressor 18 to form a refrigerating room cooling refrigerating cycle. .

At this time, by operating the refrigerating compartment fan 31 simultaneously with the operation of the compressor 18, the air in the refrigerating compartment 3 is sucked from the refrigerating compartment suction port 8 and is passed through the refrigerating compartment cooler 23 to exchange heat. The cooled air is discharged from the refrigerator outlet 32 to the refrigerator 3 to cool the refrigerator 3.

At any time during which the compressor 18 is stopped, the refrigerating room fan 31 is operated so that the refrigerating room 3
The air having a temperature exceeding 0 ° C. is passed through the refrigerator cooler 23. At this time, the frost formed on the refrigerator compartment cooler 23 is defrosted while increasing the absolute humidity of the air passing through the refrigerator compartment cooler 23.

The air having the increased absolute humidity is discharged from the refrigerator outlet 32.

When the freezing room 2 is cooled, when the freezing room 2 reaches a certain set temperature or higher, the compressor 18 is activated, and the circulation of the flammable refrigerant in the refrigeration cycle is started. At 19, the refrigerant is condensed by heat exchange with the outside air, flows through the low evaporating temperature reducing mechanism 21 through the switching valve 20 to the freezing room cooler 24, and is sucked into the compressor 18. Become.

When the freezer compartment fan 28 is operated at the same time as the operation of the compressor 18, the air in the freezer compartment 2 is sucked from the freezer compartment suction port 7 and is passed through the freezer compartment cooler 24 to exchange heat and cool. The cooled air is discharged from the freezer compartment outlet 29 into the freezer compartment 2 to cool the freezer compartment 2. At this time, since the air flowing through the freezer compartment cooler 24 is air only in the freezer compartment 2, the amount of frost on the freezer compartment cooler 24 is reduced.

Then, immediately after the compressor 18 has stopped after an elapse of an arbitrary time, or if the compressor 18 is in operation, the compressor 18 is stopped, and at the same time, the defrosting means 26 is operated, and the freezing room fan 28 is stopped. The operation of the defrosting unit 26 causes the defrosting unit to generate heat, and the heat generated by the defrosting unit 26 transfers heat to the freezer compartment cooler 24 to perform defrosting. At this time, at the start of defrosting,
Normally, the refrigerant flows backward from the refrigerator cooler 23 to the refrigerator cooler 24 whose evaporation temperature is lower than that of the refrigerator cooler 23, but in the present embodiment, the check valve 25 prevents the refrigerant from flowing back. Defrosting is performed.

Furthermore, the freezer compartment cooler 2 of the defrosting means 26
By the heating of 4, the refrigerant inside the piping of the freezer compartment cooler 24 is also heated, gasified and discharged from the freezer compartment cooler 24, and even the discharged refrigerant flows back through the check valve 25. There is no.

When the temperature of the freezer compartment cooler 24 and its surroundings reaches a temperature exceeding 0 ° C. at which the frost melts, the defrosting is completed. At this time, the defrosted water that has melted and becomes water is appropriately stored in the evaporating dish 33, and is evaporated using the waste heat generated by the operation of the compressor 18 accompanying the cooling after the completion of the defrosting, and is evaporated to the outside air. Is discharged.

Thus, when the freezer compartment cooler 24 is being defrosted, the amount of frost to be removed by the defrosting means 26 is reduced by reducing the amount of frost formed in the freezer compartment cooler 24, and the check valve is also provided. 25, it is not necessary to heat the wasteful refrigerant flowing backward to the freezer compartment cooler 24.
Energy consumption by reducing the power consumption of
Since the calorific value of the defrosting means 26 can be reduced to a calorific value that is lower than the ignition temperature of the flammable refrigerant, the environment in which the flammable refrigerant leaks into the installation atmosphere of the defrosting means 26 while maintaining the defrosting ability at or above the conventional level. Even when defrosting is performed below, the possibility of ignition of the combustible refrigerant can be reduced.

(Embodiment 2) Embodiment 2 according to the present invention will be described with reference to the drawings. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 3 is a time chart of the refrigerator according to the second embodiment of the present invention.

As shown in FIG. 3, the switching valve 20 is open until the refrigerant flows through the refrigerator cooler 23 or the freezer cooler 24 until immediately before defrosting.
With the operation of the defrosting means 26, which is the start of the defrosting of 4, the compressor 18 is stopped, and the switching valve 20 is controlled to be closed so that the refrigerant does not flow through the freezing room cooler 24. 24 is started.

[0102] Regarding the refrigerator controlled as described above,
The operation will be described below.

The heat generated by the operation of the defrosting means 26 is transferred to the freezer compartment cooler 24 to heat the freezer compartment cooler 24 to perform defrosting. At this time, the refrigerant in the freezer compartment cooler 24 is also heated.
Since there is no refrigerant flowing to the freezer compartment cooler 24, there is no refrigerant flowing from the condenser 19 through the switching valve 20 through the low evaporation temperature decompression mechanism 21 into the freezer compartment cooler 24. The amount of heating of the refrigerant in the room cooler 24 can be reduced.

Therefore, the amount of frost to be defrosted by the defrosting means 26 is reduced by the reduction of the amount of frost formed in the freezer compartment cooler 24, and the freezer compartment cooling is controlled by controlling the check valve 25 and the switching valve 20. Since it is not necessary to heat the useless refrigerant flowing into the heat exchanger 24, the amount of power consumption of the defrosting means 26 can be reduced as compared with the related art, so that energy is saved.
Can be reduced to a heat value lower than the ignition temperature of the flammable refrigerant, so that the flammable refrigerant defrosts in an environment in which the flammable refrigerant has leaked into the installation atmosphere of the defrost means 26 while maintaining the defrosting ability at or above the conventional level. Is performed, the possibility of ignition of the combustible refrigerant can be further reduced.

(Embodiment 3) Embodiment 3 according to the present invention will be described with reference to the drawings. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 4 is a time chart of the refrigerator according to the third embodiment of the present invention.

As shown in FIG. 4, during an arbitrary time immediately before the operation of the defrosting means 26, that is, immediately before the defrosting of the freezer compartment cooler 24, the switching valve 20 is operated by the refrigerating compartment cooler 23 and the freezer compartment cooler 23. The compressor 18 is operated in a state where the refrigerant does not flow to either of the coolers 24. Then, the compressor 18 is stopped simultaneously with the operation of the defrosting means 26 to perform defrosting of the freezer compartment cooler 24.

[0108] Regarding the refrigerator configured as described above,
The operation will be described below.

At an arbitrary time immediately before the operation of the defrosting means 26, that is, immediately before the defrosting of the freezer compartment cooler 24, the switching valve 20 is connected to both the refrigerator compartment cooler 23 and the freezer compartment cooler 24. By operating the compressor 18 in a state where the refrigerant does not flow, most of the refrigerant in the freezer compartment cooler 24 is compressed and stored in the condenser 19 by the compressor 18. Thereafter, simultaneously with the stop of the compressor 18, the defrosting means 26 operates, and the freezing room cooler 24 starts defrosting in a state where the refrigerant in the pipe is extremely small.

Thus, the amount of frost to be defrosted by the defrosting means 26 is reduced by the reduction of the amount of frost formed in the freezer compartment cooler 24. In addition to the control of the check valve 25 and the switching valve 20, defrosting is performed. By closing the previous switching valve 20 and operating the compressor 18, the amount of refrigerant in the freezer compartment cooler 24 at the time of defrosting can be made extremely small, and unnecessary refrigerant heating by the defrosting means 26 can be greatly reduced. The power consumption of the defrosting means 26 can be further reduced, which is extremely energy saving, and the calorific value of the defrosting means 26 can be reduced to a heat value lower than the ignition temperature of the flammable refrigerant. Therefore, even if the defrosting is performed in an environment where the flammable refrigerant leaks into the installation atmosphere of the defrosting means 26, the possibility of ignition of the flammable refrigerant can be greatly reduced.

(Embodiment 4) Embodiment 4 according to the present invention will be described with reference to the drawings. The same components as those in the third embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 5 is a time chart of the refrigerator according to the fourth embodiment of the present invention.

As shown in FIG. 5, the defrosting of the freezer compartment cooler 24 is performed by setting the switching valve 20 so that the refrigerant does not flow to either the refrigerator compartment cooler 23 or the freezer compartment cooler 24. 18 is operated for 20 to 90 seconds and then the defrosting means 26
Is operated.

With respect to the refrigerator configured as described above,
The operation will be described below.

At the time of defrosting of the freezer compartment cooler 24, the compressor 1
8, the switching valve 20 is controlled so that the refrigerant does not flow to either the refrigerator cooler 23 or the freezer cooler 24, the freezer cooler 24 is depressurized, and the freezer cooler is reduced. The refrigerant in 24 is compressed and stored in the condenser 19. Most of the refrigerant in the freezer compartment cooler 24 is
After the operation of the compressor 18 for 20 seconds to 90 seconds before the pressure is stored and reached the upper limit of the capacity of the compressor 18,
The defrosting means 26 is operated, and the freezer compartment cooler 24 starts defrosting with the amount of refrigerant in the pipe being extremely small.

Thus, the amount of frost to be defrosted by the defrosting means 26 is reduced by the reduction of the amount of frost formed in the freezer compartment cooler 24, and the defrosting is performed in addition to the control of the check valve 25 and the switching valve 20. By closing the previous switching valve 20 and operating the compressor 18, the amount of refrigerant in the freezing compartment cooler 24 at the time of defrosting can be made extremely small, and unnecessary refrigerant heating by the defrosting means 26 can be greatly reduced. The power consumption of the defrosting means 26 can be further reduced, which is extremely energy saving, and the calorific value of the defrosting means 26 can be reduced to a calorific value lower than the ignition temperature of the flammable refrigerant, and the defrosting ability is equal to or higher than the conventional one. Even when the flammable refrigerant is defrosted in an environment in which the flammable refrigerant leaks into the installation atmosphere of the defrosting means 26 while maintaining the same, the danger due to the ignition of the flammable refrigerant can be greatly reduced. Further, the operation of the compressor 18 is 20
Since the time is from 90 seconds to 90 seconds, useless operation in which the capacity of the compressor 18 is equal to or more than the upper limit can be prevented, and at the same time, reliability of the compressor 18 due to excessive decrease in pressure can be prevented.

The operating time of the compressor 18 varies from 20 seconds to 90 seconds because of the difference in the amount of refrigerant charged, the difference in the internal volume of the piping of the freezer compartment cooler 24, and the difference in the freezer compartment cooler 24. This is because the amount of refrigerant in the freezer compartment cooler 24 changes due to the difference between the frost formation state and the evaporation temperature due to the change in outside air temperature.

(Embodiment 5) Embodiment 5 according to the present invention will be described with reference to the drawings. The same components as those in the fourth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 6 is a time chart of the refrigerator according to the fifth embodiment of the present invention.

As shown in FIG. 6, the switching valve 20 is opened so that the refrigerant from the condenser 19 flows to the freezer compartment cooler 24 before the defrosting means is completed.

With respect to the refrigerator controlled as described above,
The operation will be described below.

When the switching valve 20 is opened so that the refrigerant from the condenser 19 flows to the freezer compartment cooler 24 before the end of the defrosting means 26 at the end of the defrosting operation, the switching valve 20 is compressed and stored in the condenser 19. The high-temperature and high-pressure refrigerant flows into the freezer compartment cooler 24, and the inside of the freezer compartment cooler 24 is lower than the condenser 19. The cooler 24 is warmed and partially condenses in the freezer compartment cooler 24 to remove heat from the frost, thereby contributing to defrosting. Thereafter, the switching valve 20 continues defrosting while the condenser 19 and the freezer compartment cooler 24 are in communication with each other, and with time, the low pressure side including the freezer compartment cooler 24 and the condenser 19 are connected.
When the pressure difference with the high pressure side including the pressure becomes small and the pressure difference becomes small to some extent, the temperature of the freezer compartment cooler 24 and the surroundings becomes higher than a certain temperature exceeding 0 ° C. at which frost melts, and defrosting is completed. After the completion of the defrosting, the compressor 18 starts smoothly because the pressure difference between the front and rear is very small, and the cooling of the freezing compartment 2 is restarted.

Accordingly, the amount of frost to be defrosted by the defrosting means 26 is reduced by the reduction of the amount of frost formed in the freezer compartment cooler 24, and the defrosting is performed in addition to the control of the check valve 25 and the switching valve 20. By closing the previous switching valve 20 and operating the compressor 18, the amount of refrigerant in the freezing compartment cooler 24 at the time of defrosting can be made extremely small, and unnecessary refrigerant heating by the defrosting means 26 can be greatly reduced. The power consumption of the defrosting means 26 can be further reduced, which is extremely energy saving, and the calorific value of the defrosting means 26 can be reduced to a calorific value lower than the ignition temperature of the flammable refrigerant, and the defrosting ability is equal to or higher than the conventional one. Even when the flammable refrigerant is defrosted in an environment in which the flammable refrigerant leaks into the installation atmosphere of the defrosting means 26 while maintaining the same, the danger due to the ignition of the flammable refrigerant can be greatly reduced. Further, the compressor 18 after the defrost is completed.
Defrost means 2 at the time of defrosting because the start of the operation can be performed smoothly.
Since the temperature rise of the freezing compartment 2 accompanying the heating of 6 can be quickly cooled, deterioration of the stored food due to the temperature rise of the freezing compartment 2 during defrosting can be prevented.

(Embodiment 6) Embodiment 6 of the present invention will be described with reference to the drawings. The same components as those in the third embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 7 is a time chart of the refrigerator according to the sixth embodiment of the present invention.

As shown in FIG. 7, when the defrosting means 26 is operating during the defrosting of the freezer compartment cooler 24, the switching valve 20 is set so that the refrigerant can flow through the refrigerator compartment cooler 23. It is controlled to a position where the refrigerator cooler 23 and the condenser 19 communicate with each other.

With respect to the refrigerator configured as described above,
The operation will be described below.

With the compressor 18 operating, the switching valve 20
Is controlled so that the refrigerant does not flow from the condenser 19, and the refrigerant inside the pipes of the refrigerator cooler 23 and the freezer cooler 24 is compressed and stored in the condenser 19. Then, the compressor 18
Is stopped and the switching valve 20 is controlled so as to communicate with the refrigerator cooler 23, and at the same time, the defrosting means 26 is operated.
The pressure difference between the suction side of the compressor 18 communicating with the refrigerator cooler and the discharge side of the compressor 18 communicating with the condenser 19 becomes smaller, and the refrigerator cooler introduces refrigerant into the piping. Frost is reduced, and the freezer compartment cooler 24 and its surroundings reach a certain temperature exceeding 0 ° C. at which the frost melts, and the defrost ends. After the completion of defrosting, the switching valve 20 is connected to the condenser 19
And the freezer compartment cooler 24 are controlled to communicate with each other, and at the same time, the compressor 18 operates smoothly in a state where the high and low pressure differential pressures are small, thereby rapidly cooling the freezer compartment 2.

Accordingly, the amount of frost to be defrosted by the defrosting means 26 is reduced by the reduction of the amount of frost formed in the freezer compartment cooler 24, and the defrosting is performed in addition to the control of the check valve 25 and the switching valve 20. By closing the previous switching valve 20 and operating the compressor 18, the amount of refrigerant in the freezer compartment cooler 24 at the time of defrosting can be reduced to a very small amount, and wasteful refrigerant heating by the defrosting means 26 can be greatly reduced. The amount of power consumption of the defrosting means 26 can be reduced, which is extremely energy saving, and the calorific value of the defrosting means 26 can be reduced to a calorific value lower than the ignition temperature of the flammable refrigerant. Even when the flammable refrigerant is defrosted in an environment in which the flammable refrigerant has leaked into the installation atmosphere of the defrosting means while maintaining the same, the risk of ignition of the flammable refrigerant can be greatly reduced. Further, since the compressor 18 can be started smoothly after the completion of the defrosting, the temperature rise of the freezing compartment 2 accompanying the heating of the defrosting means 26 at the time of defrosting can be quickly cooled. The deterioration of the preserved food due to the temperature rise can be prevented.

(Embodiment 7) Embodiment 7 of the present invention will be described with reference to the drawings. The same components as those in the sixth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 8 is a time chart of the refrigerator according to the seventh embodiment of the present invention.

As shown in FIG. 8, when the defrosting means 26 is operating during the defrosting of the freezer compartment cooler 24, the switching valve 20 is set so that the refrigerant can flow through the refrigerator compartment cooler 23. The position where the refrigerator cooler 23 and the condenser 19 are communicated is controlled, and the compressor 18 is operating.

With respect to the refrigerator configured as described above,
The operation will be described below.

When the compressor 18 is operated, the switching valve 20
Is controlled so that the refrigerant does not flow from the condenser 19, and the refrigerant inside the pipes of the refrigerator cooler 23 and the freezer cooler 24 is compressed and stored in the condenser 19. Then, the compressor 18
When the defrosting means 26 is operated at the same time as controlling the switching valve 20 to communicate with the refrigerator compartment cooler 23 in the operating state, the refrigerator compartment cooler is cooled by the refrigerant flow to cool the refrigerator compartment. The freezer compartment cooler is defrosted with less refrigerant in the piping, and the freezer compartment cooler 24 and its surroundings reach a certain temperature exceeding 0 ° C. at which the frost melts, and the defrosting is completed. After the completion of the defrosting operation, the switching valve 20 is controlled to communicate with the freezer compartment cooler 24 in a state where the refrigerator compartment 3 is sufficiently cooled, and the compressor 18 continues to operate, so that the freezer compartment is operated. Cool 2

From this, the amount of frost to be defrosted by the defrosting means 26 is reduced by the reduction of the amount of frost formed in the freezer compartment cooler 24, and the defrosting is performed in addition to the control of the check valve 25 and the switching valve 20. By closing the previous switching valve 20 and operating the compressor 18, the amount of refrigerant in the freezing compartment cooler 24 at the time of defrosting can be made extremely small, and unnecessary refrigerant heating by the defrosting means 26 can be greatly reduced. The power consumption of the defrosting means 26 can be further reduced, which is extremely energy saving, and the calorific value of the defrosting means 26 can be reduced to a calorific value lower than the ignition temperature of the flammable refrigerant, and the defrosting ability is equal to or higher than the conventional one. Even if defrosting is performed in an environment where the flammable refrigerant has leaked to the installation atmosphere of the defrosting means while maintaining, in addition to being able to greatly reduce the risk of ignition of the flammable refrigerant, after defrosting is completed Compressor 18 starts smoothly Defrosting means 26 at the time of defrosting from Rukoto
Can quickly cool the temperature rise of the freezer 2 due to the heating of
Deterioration of the preserved food due to the temperature rise in the freezing compartment 2 during defrosting can be prevented. Furthermore, since the refrigerator compartment 3 is sufficiently cooled when the refrigerator compartment 2 is cooled after defrosting, it is possible to prevent food deterioration due to insufficient cooling of the refrigerator compartment 3 due to the cooling of the refrigerator compartment 2.

(Eighth Embodiment) An eighth embodiment according to the present invention will be described with reference to the drawings. The same components as those in the conventional example are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 9 is a refrigeration system diagram of a refrigerator according to the eighth embodiment of the present invention.

As shown in FIG. 9, 18 is a compressor, 19 is a condenser, 26 is defrosting means for defrosting frost adhering to the evaporator 10, 34 is a decompression mechanism, and A flammable refrigerant (not shown) is sealed in a refrigeration cycle in which the condenser 19, the pressure reducing mechanism 21, and the evaporator 10 are functionally connected in a ring.

[0139] Regarding the refrigerator configured as described above,
The operation will be described below.

The operation of the compressor 18 cools the evaporator 10 of the refrigerating cycle, and the air in the refrigerator passes through the cooled evaporator 10 by the fan 11 that operates simultaneously with the operation of the compressor 18, and the evaporator 10 is cooled. The inside of the refrigerator is cooled by discharging the cold air that has been heat-exchanged into the refrigerator. At this time, frost forms on and around the surface of the evaporator 10, and the frost increases as time passes. If the heat transfer is reduced and defrosting is not performed, the inside of the refrigerator will be insufficiently cooled. Therefore, after elapse of an arbitrary operation time of the compressor 18, the defrosting means 2
6 is operated to periodically defrost the frost on the evaporator 10. At the time of defrosting, the defrosting means 26 generates heat at a temperature lower than the ignition temperature of the flammable refrigerant used in the refrigeration cycle to defrost the evaporator 10, and the completion of defrosting is detected by detecting means (not shown). Is detected, the defrosting means 26 is stopped, and non-cooling in the refrigerator due to frosting is periodically prevented.

Further, since the flammable refrigerant heated together with the evaporator 10 during the defrosting of the evaporator 10 has a higher thermal conductivity than the conventional HCF refrigerant, it is possible to reduce the temperature of the defrosting means 26 by lowering the calorific value. It is possible.

Therefore, even if defrosting is performed in the event that the flammable refrigerant in the refrigeration cycle leaks into the refrigerator, the defrosting means 26 will remain below the ignition temperature of the flammable refrigerant used in the refrigeration cycle. Temperature, so that the possibility of ignition is reduced.

In the present embodiment, the number of the evaporator 10 is one. However, the same effect can be obtained even when a plurality of the evaporators 10 are installed. Needless to say, the same effect can be obtained widely for such a thing.

(Embodiment 9) Embodiment 9 of the present invention will be described with reference to the drawings. The same components as those in the eighth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 10 is a sectional view of a main part of a refrigerator according to the ninth embodiment of the present invention.

As shown in FIG. 10, 35 is a defrosting means 26.
, A first glass tube 36, a second glass tube inside the first glass tube 35, and an inner periphery 37 of the first glass tube 35 and an outer periphery of the second glass tube 36. And a heater wire made of a metal resistor between the second glass tube 3
6, a cap for preventing defrost water from entering the inside of the glass tube 20, a cap 39 for a lead wire for conducting electricity to the heater wire 37, and a cap 40 for the second Is the internal space of the glass tube of
Is a communication port that communicates the internal space 40 provided in the cap 38 with the outside.

With respect to the refrigerator configured as described above,
The operation will be described below.

When the defrosting means 26 operates, the heater wire 37
Generates heat due to Joule heat due to energization. Then, a part of the heat is radiated to the outside through the first glass tube 35, and the rest is radiated to the internal space 40 through the second glass tube 36, and is radiated to the outside from the communication port 41 of the cap 38 by convection. In the related art, since there is no second glass tube 36, the heat is only radiated through the first glass tube 35 as a heat dissipation path. Therefore, in the present embodiment, the temperature of the heater wire 37 is lower than in the related art.

As described above, the heat radiation from the heater wire 37 is secured more than before, and the evaporator 10 and its surroundings are defrosted at a low temperature.

Further, even if the flammable refrigerant leaks in the event that the heater wire 37 rises to the ignition temperature of the flammable refrigerant for some reason, the first glass tube 35 and the second glass tube 36 will not leak. Since the volume of space around the enclosed heater wire 37 is small, the amount of combustible refrigerant flowing into the vicinity of the heater wire 37 is small, and the amount of air containing oxygen necessary for the combustible refrigerant to burn is small. Does not ignite from

Accordingly, the heater wire 37 can be set to a temperature lower than the ignition temperature of the flammable refrigerant while securing the defrosting ability equal to or higher than the conventional one, and the flammable refrigerant is removed when it leaks into the atmosphere of the defrost means 26. Even if frost is performed, the possibility of ignition can be reduced.

(Embodiment 10) Embodiment 10 of the present invention will be described with reference to the drawings. In addition,
The same components as those in the eighth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 11 is a sectional view of a main part of a refrigerator according to the ninth embodiment of the present invention.

As shown in FIG. 11, reference numeral 42 denotes a glass tube,
Reference numeral 3 denotes glass beads filled around the heater wire 37 inside the glass tube 42.

With respect to the refrigerator configured as described above,
The operation will be described below.

When the defrosting means 26 operates, the heater wire 37
Generates heat due to Joule heat due to energization. Then, heat is radiated from the glass tube 42 to the outside through the glass beads 43. Conventionally, the interior of the glass tube 42 is air, and since the glass beads have a very good thermal conductivity to air, the heat conduction from the heater wire 37 to the glass tube 42 is very good.
Since the heat generation is the same and the heat radiation is promoted, the temperature of the heater wire 37 decreases.

As described above, even if the amount of heat generated by the defrosting means 26 is the same, the heat radiation from the heater wire 37 is more than conventional, and the evaporator 10 and its surroundings are defrosted at a low temperature.

Furthermore, if the heater wire 37 rises above the ignition temperature of the flammable refrigerant for some reason, even if the flammable refrigerant leaks, even if the flammable refrigerant leaks,
Since the volume of the surrounding space is very small, the amount of the flammable refrigerant flowing into the glass tube 42 and coming into contact with the heater wire 37 is extremely small, and the amount of air containing oxygen necessary for the flammable refrigerant to burn is reduced. It does not ignite because it is small.

Accordingly, the heater wire 37 can be set to a temperature lower than the ignition temperature of the flammable refrigerant while securing the defrosting ability equal to or higher than the conventional one, and the flammable refrigerant is removed when it leaks into the atmosphere of the defrost means 26. Even if frost is performed, the possibility of ignition can be reduced.

Embodiment 11 Embodiment 11 of the present invention will be described with reference to the drawings. In addition,
The same components as those in the tenth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 11 is a sectional view of a main part of a refrigerator according to Embodiment 11 of the present invention.

The glass beads 43 filled in the glass tube 42 shown in FIG. 11 are not shown but are transparent.

[0163] Regarding the refrigerator configured as described above,
The operation will be described below.

When the defrosting means 26 operates, the heater wire 37
Generates heat due to Joule heat due to energization. The heat of the heater wire 37 is radiated to the outside from the glass tube 42 through the glass beads 43 by conduction, and a part of the heat is absorbed by the glass beads 43 and transmitted to the glass tube 42 to radiate heat to the outside while the rest is made of glass. The heat is transmitted directly to the outside through the beads 43. Thus, the glass beads 43
In addition to the good heat conduction, the transparent material transmits heat rays due to the radiation of the heater wire 37 because it is transparent, so that heat radiation from the heater wire 37 to the outside is promoted and the temperature is further reduced. In addition, even if the flammable refrigerant leaks when the heater wire 37 rises to the ignition temperature of the flammable refrigerant for some reason, the space volume around the heater wire 37 in the glass tube 42 is very small. Since the amount of the flammable refrigerant flowing into the glass tube 42 and coming into contact with the heater wire 37 is extremely small, the flammable refrigerant does not ignite because the amount of oxygen-containing air required for combustion is small.

Thus, the heater wire 37 can be set to a temperature lower than the ignition temperature of the flammable refrigerant while securing the defrosting ability equal to or higher than the conventional one, and the flammable refrigerant is removed when it leaks into the atmosphere of the defrost means 26. Even if frost is performed, the possibility of ignition can be reduced.

(Twelfth Embodiment) A twelfth embodiment of the present invention will be described with reference to the drawings. In addition,
The same components as those in the tenth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 12 is a sectional view of a main part of a refrigerator according to Embodiment 11 of the present invention.

As shown in FIG. 12, reference numeral 44 denotes a glass tube.
It is a gap other than the glass beads 43 in the inside, and is a gap 44 in which the filling amount of the glass beads 43 can be less than 100%.

[0169] The refrigerator configured as described above
The operation will be described below.

When the defrosting means 26 operates, the heater wire 37
Generates heat due to Joule heat due to energization. Then, the heater wire 37 radiates heat from the glass tube 42 to the outside through the glass beads 43. Conventionally, the inside of the glass tube 42 is air,
Since the glass beads 43 have a very good thermal conductivity with respect to air, the heat conduction from the heater wire 37 to the glass tube 42 is very good, and the heat generation is the same and heat radiation is promoted. Decreases the temperature. Further, even if the flammable refrigerant leaks in the event that the heater wire 37 rises to the ignition temperature of the flammable refrigerant for some reason, the glass tube 4
Since the volume of space around the heater wire 37 in the tube 2 is very small, the amount of flammable refrigerant flowing into the glass tube 42 and coming into contact with the heater wire 37 is extremely small, and is necessary for the flammable refrigerant to burn. Does not ignite due to small amount of air containing oxygen.

Further, the heater wire 37 thermally expands as the temperature rises. At this time, the expansion is smoothly absorbed by the gap 44.

Accordingly, the heater wire 37 can be set to a temperature lower than the ignition temperature of the flammable refrigerant while securing the defrosting ability equal to or higher than the conventional one, and the flammable refrigerant is removed when it leaks into the atmosphere of the defrost means 26. Even if frost is performed, the possibility of ignition can be reduced.

In addition, defects such as disconnection due to suppression of thermal expansion of the heater wire 37 can be prevented, and long-term reliability can be ensured.

(Thirteenth Embodiment) A thirteenth embodiment of the present invention will be described with reference to the drawings. In addition,
The same components as those in the tenth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 11 is a sectional view of a main part of a refrigerator according to Embodiment 13 of the present invention.

As shown in FIG. 11, the cap 38 is attached to the glass tube 42 with both ends sealed.

[0177] Regarding the refrigerator configured as described above,
The operation will be described below.

At the time of defrosting, the heater wire 37 of the defrosting means 26 generates heat, and radiates heat from the glass tube 42 to the outside through the glass beads 43 having good thermal conductivity, whereby the heat of the heater wire 37 moves to the outside. The external evaporator 10 and its surroundings are defrosted.

When the temperature of the evaporator 10 and its surroundings becomes somewhat higher than 0 ° C., which is the melting point of frost, the heater wire 3
Heating is stopped due to the stop of energization of 7, and the heater wire 37 rapidly drops to a temperature corresponding to the surrounding temperature. At this time, since both ends of the glass tube 42 are sealed, high-humidity air after defrost does not flow into the glass tube 42 due to temperature balance between the inside and the outside of the glass tube 42.

From the above, it is possible that the high-humidity air flowing into the glass tube 42 is condensed and becomes water to be stored in the glass tube 42 due to the temperature decrease of the defrosting means 26 accompanying the cooling in the refrigerator after the completion of the defrosting. There is no.

As described above, the temperature reduction of the defrosting means 26 and the reduction of the space volume in the glass tube 42 due to the promotion of heat radiation by the glass beads having good heat conduction ensure the defrosting ability equal to or higher than the conventional one. The heater wire 37 can be set at a temperature lower than the ignition temperature of the flammable refrigerant, and the possibility of ignition can be further reduced even if defrosting is performed when the flammable refrigerant leaks into the atmosphere of the defrosting means 26.

In addition, the amount of water in the glass tube 42 can be extremely reduced, and failure such as disconnection due to corrosion of the heater wire 37 can be prevented, and long-term reliability can be ensured.

(Embodiment 14) Embodiment 14 of the present invention will be described with reference to the drawings. In addition,
The same components as those in the eighth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 13 is a sectional view of a main part of a refrigerator in a fourteenth embodiment of the present invention.

As shown in FIG. 13, 45 is a defrosting means 26.
Is a defrosting means cooling fan installed in the vicinity of.

With respect to the refrigerator configured as described above,
The operation will be described below.

At the time of defrosting, when the defrosting means 26 reaches a certain temperature at the same time as the defrosting means 26 or several minutes later, the defrosting means cooling fan 45 is operated. By the operation of the defrosting means cooling fan 45, heat exchange between the defrosting means 26 and the outside is promoted and the attained temperature decreases, and the high-temperature air which has exchanged heat is stirred around the evaporator 10 to perform defrosting with high capacity.

Then, before or simultaneously with the completion of the defrost, the cooling fan 45 for the defrost means is stopped, and the operation of the defrost means 26 is stopped when the defrost is completed.

Further, by providing a defrosting means cooling fan 45 separately from the in-compartment cooling fan 11, it is possible to prevent high-temperature air from flowing out due to heating of the defrosting means 26 during defrosting to the inside of the compartment where food is stored. it can.

From this, the defrosting means 26 can lower the temperature and further improve the defrosting ability, thereby lowering the heat generation and further lowering the temperature. While securing the temperature, the heater wire 37 can be set to a temperature lower than the ignition temperature of the flammable refrigerant, and the possibility of ignition can be further reduced even if defrosting is performed when the flammable refrigerant leaks into the atmosphere of the defrosting means 26.

(Embodiment 15) Embodiment 15 according to the present invention will be described with reference to the drawings. In addition,
The same components as those in the eighth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 14 is a sectional view of a main part of a refrigerator according to the fifteenth embodiment of the present invention.

As shown in FIG. 14, reference numeral 46 denotes a glass tube.
Is a radiation promoting material coated on the surface of

With respect to the refrigerator configured as described above,
The operation will be described below.

At the time of defrosting, the heater wire 37 generates heat by the operation of the defrosting means 26. The heat generated by the heater wire 37 is transmitted to the glass tube 42 through gas around the heater wire 37, and the temperature of the glass tube 42 rises. Further, a part of the radiant heat ray of the heater wire 37 is transmitted directly from the heater wire 37 to the glass tube 42 and is absorbed by the glass tube 42 to increase the temperature, and the remainder is transmitted through the glass tube 42 and absorbed by the radiation promoting material 46. The temperature rises. As a result, the temperature of the glass tube 42 and the radiation enhancer 46 whose temperature has risen increases due to the effect of promoting the radiation radiation of the radiation enhancer 46 itself on the surface, and the temperature decreases. Thus, the temperature of the heater wire 37 inside the glass tube 42 also decreases.

From this, it is possible to set the heater wire 37 to a temperature lower than the ignition temperature of the flammable refrigerant while securing the defrosting ability equal to or higher than the conventional one, and to remove the flammable refrigerant when it leaks into the atmosphere of the defrost means 26. Even if frost is performed, the possibility of ignition can be reduced.

Further, since it is only necessary to coat the radiation promoting material 45 on the surface of the glass tube 42, the production is simple and inexpensive.

(Embodiment 16) Embodiment 16 of the present invention will be described with reference to the drawings. In addition,
The same components as those in the eighth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 14 is a sectional view of a main part of a refrigerator according to the sixteenth embodiment of the present invention.

As shown in FIG. 14, the radiation enhancer 46 on the surface of the glass tube 42 is transparent.

[0201] With respect to the refrigerator configured as described above,
The operation will be described below.

At the time of defrosting, the heater wire 37 generates heat by the operation of the defrosting means 26. The heat generated by the heater wire 37 is transmitted to the glass tube 42 through the gas around the heater wire 37, and the temperature of the glass tube 42 rises.

Further, a part of the radiant heat rays of the heater wire 37 is transmitted directly from the heater wire 37 to the glass tube 42 and is absorbed by the glass tube 42 to increase the temperature.
, And further through the transparent radiation promoting material 46 to be directly radiated to the outside. Accordingly, the amount of transmission of the radiant heat rays directly from the heater wire 37 to the outside increases, so that the temperature rise of the glass tube 42 is reduced, and the temperature-raised glass tube 42 is directed to the outside by the radiation promoting material 46 on the surface. The heat radiation by radiation increases and the temperature decreases. Thus, the temperature of the heater wire 37 inside the glass tube 42 also decreases.

From this, it is possible to set the heater wire 37 to a temperature lower than the ignition temperature of the flammable refrigerant while securing the same or higher defrosting ability as before, and to remove the flammable refrigerant when it leaks into the atmosphere of the defrost means 26. Even if frost occurs, the possibility of ignition can be reduced, making it simple and inexpensive to manufacture.

(Embodiment 17) Embodiment 17 of the present invention will be described with reference to the drawings. In addition,
The same components as those in the eighth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 15 is a sectional view of a main part of a refrigerator in a seventeenth embodiment of the present invention, and FIG. 16 is a sectional view of a defrosting means.

As shown in FIGS. 15 and 16, reference numeral 47 denotes a flange of the roof 16;
, B is the width of the roof 16, and a is greater than b. Arrows indicate the flow of air in the vicinity of the defrosting means 26.

[0208] Regarding the refrigerator configured as described above,
The operation will be described below.

At the time of defrosting, the air near the defrosting means 26 is warmed by the heat generated by the defrosting means 26 and moves to the upper evaporator along the flange 47 of the roof 16 as shown by the arrow, and the frost of the evaporator 10 is removed. In addition to the heat exchange, the flammable refrigerant having good thermal conductivity in the pipe of the evaporator 10 is heated. Thereby, the hot air is cooled and the frost melts.

As described above, since the inside of the pipe of the evaporator 10 is a flammable refrigerant having good heat conductivity and the depth dimension a of the evaporator is larger than the width dimension b of the roof 16, it is heated by the defrosting means 26. The high-temperature air leaking from the flange 47 of the roof 16 is smoothly transmitted to the evaporator 10, so that defrosting is performed efficiently. Since the defrosting ability is improved in this manner, the defrosting means 26 can reduce the amount of heat generation, and can lower the temperature by reducing the amount of heat generation.

Further, when the freezing room 2 or the refrigerator room 3 is cooled, the roof 16 hinders the air path, but the evaporator depth dimension a is
6, the ventilation to the evaporator 10 is good, and shortage of cooling capacity can be prevented.

From this, it is possible to set the heater wire 37 to a temperature lower than the ignition temperature of the flammable refrigerant while securing the defrosting ability equal to or higher than the conventional one, and to remove the flammable refrigerant when it leaks into the atmosphere of the defrost means 26. Even if frost is performed, the possibility of ignition can be reduced.

In addition, it is possible to prevent deterioration of stored food due to insufficient cooling during cooling.

(Eighteenth Embodiment) An eighteenth embodiment according to the present invention will be described with reference to the drawings. In addition,
The same components as those in the eighth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 17 is a cross-sectional view of a main part of a refrigerator according to Embodiment 18 of the present invention, and FIG. 18 is a cross-sectional view of a main part of a defrosting means.

As shown in FIGS. 17 and 18, reference numeral 48 denotes a metal pipe which is a component of the defrosting means 26, reference numeral 49 denotes an electrically insulating material, and reference numeral 50 denotes a water tray provided with heating means.

With respect to the refrigerator configured as described above,
The operation will be described below.

At the time of defrosting, the defrosting means 26 and the heating means attached to the water pan 50 with heating means generate heat and the temperature rises, and the defrosting means 26 defrosts the frost deposited on itself and evaporates. The evaporator 10 is defrosted by heating the evaporator 10. Here, a part of the defrost water which has not been discharged during the previous defrost and remains in the water receiving tray with heating means 50 becomes ice during cooling and remains.

[0219] Since the defrosting means 26 and the water tray 50 with heating means are installed so that heat transfer with frost and ice is improved, most of the heat generated by the defrosting means 26 and water tray 50 with heating means is reduced. Since it is absorbed by frost and ice, defrosting is performed at a temperature slightly higher than the melting point of frost and ice. When the defrosting is completed, the temperatures of the defrosting means 26 and the water receiving tray 50 with the heating means also gradually rise, but the operation is stopped by the completion of the defrosting, so that the temperature does not rise.

Further, since the refrigerant in the evaporator 10 which is heated simultaneously with the frost is a flammable refrigerant having good heat conductivity, the defrosting efficiency is further improved.

From this, in addition to lowering the temperature, the defrosting means 26 can improve the defrosting ability, thereby lowering the heat generation and lowering the temperature. While ensuring the defrosting capacity of
The heater wire 37 can be set at a temperature lower than the ignition temperature of the flammable refrigerant, and the possibility of ignition can be further reduced even if defrosting is performed when the flammable refrigerant leaks into the atmosphere of the defrosting means 26.

In addition, the evaporator 10 and the defrost water around the evaporator 10 that have fallen into the water pan 50 with heating means can be smoothly discharged to the outside. With the increase, the ventilation resistance of the evaporator 10 can be prevented from increasing and insufficient cooling can be prevented, so that deterioration of food can be prevented.

(Embodiment 19) Embodiment 19 of the present invention will be described with reference to the drawings. In addition,
The same components as those in the eighth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 19 is a sectional view of a main part of a refrigerator according to a nineteenth embodiment of the present invention.

As shown in FIG. 19, reference numeral 51 denotes an auxiliary heater installed at a position farthest from the defrosting means 26 around the evaporator 10.

With respect to the refrigerator configured as described above,
The operation will be described below.

At the same time as the start of defrosting, the defrosting means 26 operates, and at the same time as the start of defrosting or after an elapse of an arbitrary time, the auxiliary heater 51 is energized to generate heat.

The heat generated by the defrosting means 26 causes the evaporator 10 to transmit heat from the portion close to the defrosting means 26 to melt the frost, and at the same time, the heat generated by the auxiliary heater 51 to prevent the heat from being transmitted from the defrosting means 26 to the distant portion. Since the frost is defrosted by heating the frost, it is possible to reduce the calorific value of the defrosting means 26 when performing defrosting in the same time as the conventional method,
In addition, since the auxiliary heater 51 is in contact with the evaporator 10, the temperature of the auxiliary heater 51 becomes a low temperature close to 0 ° C., which is the melting point of frost, during defrosting.

From this, it is possible to reduce the temperature below the ignition temperature of the flammable refrigerant while maintaining the same defrosting capacity as before, and to perform defrosting when the flammable refrigerant leaks into the atmosphere of the defrosting means 26. In addition, the risk of ignition can be further reduced, and the defrosting means 26 is inexpensive because it is only necessary to reduce the calorific value by using a defrosting tube 15 equivalent to the conventional one.

Embodiment 20 Embodiment 20 according to the present invention will be described with reference to the drawings. In addition,
The same reference numerals are given to the same components as those in the related art, and the detailed description is omitted.

FIG. 20 is a refrigeration system diagram of a refrigerator according to a twentieth embodiment of the present invention.

As shown in FIG. 20, reference numeral 52 denotes an evaporator 10 which bypasses the condenser 19 and the pressure reducing device 34 from the compressor 18.
Is a valve provided in the middle of the path of the bypass pipe 52.

With respect to the refrigerator configured as described above,
The operation will be described below.

During normal cooling of the refrigerator, the valve 53 is closed, and the refrigerant compressed by the compressor 18 is cooled and condensed by the condenser 19 and is evaporated under reduced pressure through the decompression device 34 to evaporate the evaporator 10. Cooling. The refrigerant is heated by exchanging heat with the air in the evaporator 10 to cool the air. The cooled air is carried into the refrigerator to cool foods and the like in the refrigerator. The heated refrigerant returns to the compressor 18.

Next, since the valve 53 is opened at the time of defrosting, the high-temperature hot gas refrigerant compressed by the compressor 18 flows to the valve 53 having a small resistance with respect to the resistance of the pressure reducing device 34, and evaporates. Into the vessel 10. Then, the hot gas refrigerant exchanges heat with frost adhering to the surface of the evaporator 10, thereby lowering the temperature of the hot gas refrigerant to perform defrost. Further, after the frost on the surface of the evaporator 10 is defrosted, heat from the refrigerant is transmitted from the evaporator 10 to the periphery thereof, thereby defrosting the periphery. When the defrosting of the evaporator 10 and its surroundings is completed, the valve 53 closes to provide a refrigerant path for normal refrigerator cooling, thereby cooling the refrigerator.

From this, defrosting at a very low temperature can be performed as compared with the conventional high-temperature defrosting tube heater 15, so that the flammable refrigerant is stored in a refrigerator or the like using the flammable refrigerant. Even if defrosting is performed when leaked into the inside, the possibility of ignition can be extremely reduced.

Furthermore, since heat is efficiently transferred to frost in contact with the evaporator 10 to perform heat defrosting, the defrosting can be performed very efficiently and the defrosting time can be extremely reduced.
Since the compressor 18 operates continuously during defrosting, there is no rush current due to the activation of the compressor 18 as in normal defrosting, so that energy is saved.

(Embodiment 21) Embodiment 21 of the present invention will be described with reference to the drawings. In addition,
The same components as those in the twentieth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 20 is a diagram showing a refrigeration system for a refrigerator according to the twenty-first embodiment of the present invention.

When the valve 53 shown in FIG. 20 is opened during defrosting, it is not shown, but the piping from the compressor 18 to the bypass piping 52, the bypass piping 52 and the bypass piping 5 are not shown.
Among the pipes extending from the pipe 2 to the evaporator 10, the inner diameter of the valve 53 is larger than the pipe having the smallest inner diameter.

With respect to the refrigerator configured as described above,
The operation will be described below.

During defrosting, hot gas refrigerant from the compressor 18 reaches the evaporator 10 through the valve 53.

Then, the evaporator 10 is defrosted. Valve 53
When the hot gas refrigerant passes through the valve 53, the valve 53 has a diameter equal to or larger than the inner diameter of the path up to that point, so that the valve 53 passes smoothly.

From this, defrosting at a very low temperature can be performed as compared with the conventional high-temperature defrosting tube heater 15, so that the flammable refrigerant is stored in a refrigerator or the like using the flammable refrigerant. Even if defrosting is performed when leaked into the inside, the risk of ignition can be extremely reduced.

Further, since the circulation of the hot gas refrigerant is not hindered by the valve 53, and the heat is efficiently transferred to the frost in contact with the evaporator 10 to perform the heat defrost, the defrost is performed very efficiently. That the defrosting time can be extremely reduced
Since the compressor 18 operates continuously during defrosting, there is no inrush current due to the activation of the compressor 18 as in normal defrosting.

(Embodiment 22) Embodiment 22 of the present invention will be described with reference to the drawings. In addition,
The same components as those in the twentieth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 21 is a refrigeration system diagram of a refrigerator according to a twenty-second embodiment of the present invention.

As shown in FIG. 21, reference numeral 54 denotes an evaporator inlet pipe through which a refrigerant flows into the evaporator 10, 55 denotes an evaporator outlet pipe from the evaporator 10 provided with the accumulator to the compressor 18, and arrows indicate This is the direction of air flow through the evaporator 10.

[0249] Regarding the refrigerator configured as described above,
The operation will be described below.

While the refrigerator is being cooled, the compressor 18
Then, the refrigerant flows from the evaporator inlet pipe 54 to the evaporator 10 through the pressure reducing device 34 and cools the evaporator 10. At this time, the air in the refrigerator compartment is ventilated by the fan 11 from the evaporator 10 near the evaporator inlet pipe 54 and is discharged from the evaporator 10 near the evaporator outlet pipe, so that the air is heated by the evaporator 10. Replace and cool. At this time, the air flowing from the evaporator 10 near the evaporator inlet pipe 54 is frosted on the pipes and fins of the evaporator 10 together with the heat exchange, reduces the absolute humidity, and flows downstream. The air passing through the portion of the evaporator 10 near the evaporator outlet pipe 55 has a lower temperature and a lower absolute humidity than the air at the time of inflow. For this reason, frost formation on the evaporator 10 is greatest on the upstream side of the ventilation air.

Next, when performing defrosting, the high-temperature hot gas refrigerant from the compressor 18 passes through the bypass pipe 52 and the valve 53 and flows into the pipe on the upstream side of the ventilation air of the evaporator 10 from the evaporator inlet pipe. Then, it returns to the compressor 18 from the piping on the downstream side of the ventilation air of the evaporator 10 via the evaporator outlet piping 55. At this time, the hot gas refrigerant flowing through the evaporator 10 has the hottest hot gas refrigerant flowing to the portion where frost is most frequent, defrosting and reducing the temperature of the refrigerant, and the refrigerant having the lowest temperature is the most. The evaporator 1 is circulated to the part with less frost formation.
0 Defrosts the whole evenly.

As described above, since the defrosting operation at a very low temperature can be performed as compared with the conventional high-temperature defrosting tube heater 15, the flammable refrigerant can be used in a refrigerator or the like using the flammable refrigerant. Even if defrosting is performed in the case of leakage into the storage, the risk of ignition can be extremely reduced.

Further, since the evaporator 10 can be made uniform and the heat defrosting is performed by efficiently transferring heat to the frost in contact with the evaporator 10, the defrosting can be performed very efficiently and the defrosting time can be reduced. Is extremely shortened, and since the compressor 18 operates continuously during defrosting, there is no inrush current due to the activation of the compressor 18 as in normal defrosting.

(Embodiment 23) Embodiment 23 of the present invention will be described with reference to the drawings. In addition,
The same components as those in the twentieth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 22 is a sectional view of a main part of a refrigerator according to a twenty-third embodiment of the present invention.

As shown in FIG. 22, a water receiving tray 50 with a heating means provided with a heating means is provided below the evaporator 10.

With respect to the refrigerator configured as described above,
The operation will be described below.

At the time of defrosting, at the same time as the start of defrosting, or after elapse of an arbitrary time, the heating means of the water receiving tray with heating means 50 is operated, and the water receiving tray with heating means 50 is heated.

Also, the frost adhering to the evaporator 10 due to the hot gas refrigerant is melted from the portion in contact with the evaporator 10 side,
The frost separated from the evaporator 10 on a part of the outside air falls into the water receiving tray 50 with the heating means together with the defrosted water melted as described above without being melted. At this time, since the water receiving tray with heating means 50 is heated, the frost that has fallen without being melted is also melted, and drains smoothly to the outside from the drain port.

At the time of normal cooling after the completion of defrosting, since there is no frost or defrosting water remaining in the water tray 50 with heating means,
Since the load is reduced, cooling can be performed quickly.

As described above, since defrosting at a very low temperature can be performed as compared with the conventional defrosting tube heater 15 at a high temperature, the flammable refrigerant can be used in a refrigerator or the like using a flammable refrigerant. The possibility of ignition can be extremely reduced even if defrosting is performed when leaking into the storage.

Further, since heat is efficiently transferred to frost in contact with the evaporator 10 to perform heat defrosting, the defrosting can be performed very efficiently and the defrosting time can be extremely reduced.
Since the compressor 18 operates continuously during defrosting, there is no inrush current due to the activation of the compressor 18 as in normal defrosting.

In addition, since the cooling speed at the time of cooling after defrosting is increased, deterioration of food due to temperature rise after defrosting can be prevented.

(Embodiment 24) Embodiment 24 of the present invention will be described with reference to the drawings. In addition,
The same components as those in the twentieth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 23 is a refrigeration system diagram of a refrigerator according to a twenty-fourth embodiment of the present invention.

As shown in FIG. 23, reference numeral 56 denotes a heating means attached to the evaporator outlet pipe 55 so that heat exchange is good.

[0267] Regarding the refrigerator configured as described above,
The operation will be described below.

When the outside air temperature is low during defrosting,
A part of the hot gas refrigerant which has been cooled by heat exchange with the frost of the evaporator 10 is condensed and liquefied, and flows through the evaporator outlet pipe 55.

At the same time as the start of defrosting or after an elapse of an arbitrary time, the heating means 56 is activated to activate the evaporator outlet pipe 5.
5 is heated.

[0270] The liquid refrigerant flowing through the evaporator outlet pipe 55 is heated by the heating means 56, evaporates and gasifies, and returns to the compressor 18.

From the above, defrosting at a very low temperature can be performed as compared with the conventional high-temperature defrosting tube heater 15, so that the flammable refrigerant can be used in a refrigerator or the like using a flammable refrigerant. The possibility of ignition can be extremely reduced even if defrosting is performed when leaking into the storage.

Furthermore, since heat is efficiently transferred to frost in contact with the evaporator 10 to perform heat defrosting, defrosting can be performed very efficiently and the defrosting time can be extremely reduced.
Since the compressor 18 operates continuously during defrosting, there is no inrush current due to the activation of the compressor 18 as in normal defrosting.

In addition, it is possible to prevent the compressor 18 from being damaged by the liquid bag during defrosting, and to ensure a long life.

(Twenty-Fifth Embodiment) A twenty-fifth embodiment according to the present invention will be described with reference to the drawings. In addition,
The same components as those in the twentieth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 24 is a diagram showing the throttle characteristic of the valve 53 according to Embodiment 24 of the present invention.

As shown in FIG. 24, reference numeral 54 denotes an evaporator inlet pipe through which refrigerant flows into the evaporator 10, reference numeral 55 denotes an evaporator outlet pipe from the evaporator 10 to the compressor 18, and a valve 53 controls the amount of frost. If the amount is large, the aperture is reduced, and the aperture is increased as the amount of frost decreases.

With respect to the refrigerator configured as described above,
The operation will be described below.

At the time of defrosting, if the amount of defrosting is large, the valve 5
Since the throttle amount of No. 3 is reduced, the reduced pressure amount is reduced and the circulation amount of the hot gas refrigerant is increased. Then, defrosting is gradually performed from the portion near the evaporator inlet pipe 54, which is near the inlet of the hot gas refrigerant to the evaporator 10, and as the amount of frost decreases, the throttle amount of the valve 53 increases and the hot gas The circulation amount of the refrigerant decreases, and the circulation amount of the hot gas refrigerant corresponding to the remaining frost amount flows.

[0279] From the above, defrosting at a very low temperature can be performed as compared with the conventional defrosting tube heater 15 having a high temperature. Therefore, in a refrigerator or the like using a flammable refrigerant, the flammable refrigerant is used. Even if defrosting is performed when leaking into the storage, the risk of ignition can be extremely reduced.

Furthermore, since heat is efficiently transferred to frost in contact with the evaporator 10 to perform heat defrosting, very efficient defrosting is performed and heat is efficiently transferred to perform heat defrosting. Since the defrosting is performed very efficiently and the defrosting time can be extremely reduced, and since the compressor 18 is continuously operated during the defrosting, the inrush by the activation of the compressor 18 as in the normal defrosting is performed. Since there is no current, it is very energy saving.

In addition, since the refrigerant is circulated by an amount corresponding to the formation of frost on the evaporator 10, wasteful heating of the evaporator 10 is reduced, the temperature rise in the refrigerator is reduced, and the cooling speed during cooling is increased. Therefore, deterioration of food can be prevented.

(Embodiment 26) Embodiment 26 of the present invention will be described with reference to the drawings. In addition,
The same components as those in the twenty-fifth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 25 is a refrigeration system diagram of a refrigerator according to a twenty-sixth embodiment of the present invention.

As shown in FIG. 25, reference numeral 57 denotes an evaporator outlet temperature detecting means for detecting the outlet temperature of the evaporator 10, and 58 denotes an output line for transmitting the temperature detected by the evaporator outlet temperature detecting means 57 to the valve 53. .

[0285] Regarding the refrigerator configured as described above,
The operation will be described below.

At the time of defrosting, the hot gas refrigerant flowing into the evaporator 10 performs heat exchange with the frost of the evaporator 10 to perform defrosting. At this time, the hot gas refrigerant removes heat from the frost, lowers its own temperature and partially condenses into a liquid, but when passing through the evaporator outlet pipe 55, the evaporator outlet temperature detecting means 5
7 detects the temperature at which the refrigerant becomes liquid, and reduces the amount of refrigerant circulating by reducing the throttle amount of the valve 53. The refrigerant in the evaporator 10 cannot be condensed only by the amount of heat taken when the frost is melted. The state returns to the compressor 18.

As described above, since defrosting at a very low temperature can be performed as compared with the conventional defrosting tube heater 15 having a high temperature, in a refrigerator or the like using a flammable refrigerant, the flammable refrigerant is used. The possibility of ignition can be extremely reduced even if defrosting is performed when leaking into the storage.

Furthermore, since heat is efficiently transferred to frost in contact with the evaporator 10 to perform heat defrosting, very efficient defrosting is performed, and heat is efficiently transferred to perform heat defrosting. Since the defrosting is performed very efficiently and the defrosting time can be extremely reduced, and since the compressor 18 is continuously operated during the defrosting, the inrush by the activation of the compressor 18 as in the normal defrosting is performed. Since there is no current, it is very energy saving.

In addition, it is possible to prevent the compressor 18 from being damaged by the liquid bag during defrosting, and to ensure a long life.

(Embodiment 27) Embodiment 27 of the present invention will be described with reference to the drawings. In addition,
The same components as those in the twentieth embodiment are denoted by the same reference numerals, and detailed description is omitted.

FIG. 26 is a refrigeration system diagram of a refrigerator according to a twenty-seventh embodiment of the present invention.

The compressor 18 shown in FIG. 26 has a variable number of revolutions.

With respect to the refrigerator configured as described above,
The operation will be described below.

At the time of defrosting, the hot gas refrigerant flowing into the evaporator 10 performs defrosting by exchanging heat with the frost of the evaporator 10, and the hot gas refrigerant takes heat from the frost to lower its temperature. At this time, the frost is melted in the evaporator 10 by changing the rotation speed of the compressor 18, but the hot gas refrigerant is not condensed only by the amount of heat taken from the frost, and the evaporator 10 is connected to the evaporator outlet pipe by gas. The flow returns to the compressor 18 via 55.

As described above, since defrosting at a very low temperature can be performed as compared with the conventional defrosting tube heater 15 having a high temperature, in a refrigerator or the like using a flammable refrigerant, the flammable refrigerant cannot be used. The possibility of ignition can be extremely reduced even if defrosting is performed when leaking into the storage.

Furthermore, since heat is efficiently transferred to frost in contact with the evaporator 10 to perform heat defrosting, very efficient defrosting is performed and heat is efficiently transferred to perform heat defrosting. Since the defrosting is performed very efficiently and the defrosting time can be extremely reduced, and since the compressor 18 is continuously operated during the defrosting, the inrush by the activation of the compressor 18 as in the normal defrosting is performed. Since there is no current, it is very energy saving.

In addition, it is possible to prevent damage to the compressor 18 due to liquid back during defrosting, to secure a long life, and to prevent liquid back by changing the rotation speed of the compressor 18, thereby saving energy.

[0298]

As described above, according to the first aspect of the present invention, there are provided a refrigerator main body in which a freezing compartment and a refrigerator compartment are provided independently so as to prevent convection of air, a compressor, a condenser, and a refrigerator. Refrigeration compartment cooler with high evaporation temperature, high evaporation temperature decompression mechanism with small decompression for high evaporation temperature, refrigeration compartment cooling with low evaporation temperature for refrigeration connected in parallel with refrigerator compartment cooler A low-evaporation temperature decompression mechanism with a large decompression for low-evaporation temperature, a switching valve for controlling the refrigerant not to flow simultaneously to the refrigerator-room cooler and the freezer-room cooler, and a freezer-room cooler. Since a refrigeration system in which a flammable refrigerant is sealed and a defrosting means for defrosting the freezer compartment cooler are functionally connected to the outlet with a check valve for preventing the backflow of the refrigerant, the freezer compartment is provided. During the defrosting of the refrigerator cooler, the defrosting means is removed by reducing the amount of frost on the refrigerator cooler. Since the amount of frost to be reduced is reduced, and the useless refrigerant that flows back into the freezer compartment cooler by the check valve does not need to be heated, the power consumption of the defrosting unit can be reduced as compared with the related art, which is energy saving. At the same time, since the calorific value of the defrosting means can be reduced to a calorific value that is lower than the ignition temperature of the flammable refrigerant, the environment in which the flammable refrigerant leaks to the installation atmosphere of the defrosting means while maintaining the defrosting ability at or above the conventional level. Even when defrosting is performed below, the possibility of ignition of the combustible refrigerant can be reduced.

According to the second aspect of the present invention, when defrosting the freezer compartment cooler, the switching valve is controlled so that the refrigerant does not flow into the freezer compartment cooler. Since the amount of frost to be defrosted by the defrosting means is reduced by the reduction of the amount of frost, and the useless refrigerant flowing into the freezer compartment cooler does not have to be heated by controlling the check valve and the switching valve. In addition, since the power consumption of the defrosting means can be reduced and the energy consumption is reduced, and the calorific value of the defrosting means can be reduced to a value lower than the ignition temperature of the flammable refrigerant, so that the defrosting ability is equal to or higher than the conventional one. Therefore, even if defrosting is performed in an environment in which the flammable refrigerant has leaked into the installation atmosphere of the defrosting means, the possibility of ignition of the flammable refrigerant can be further reduced.

Further, in the invention according to claim 3, when the defrosting of the freezer compartment cooler is performed, the switching valve is controlled so that the refrigerant does not flow into both the refrigerator compartment cooler and the freezer compartment cooler. Since the defrosting means is operated after operating the compressor for an arbitrary time above, the amount of frost to be defrosted by the defrosting means is reduced due to the reduction of the amount of frost formed in the freezer cooler, and the check valve By closing the switching valve and operating the compressor before defrosting in addition to controlling the switching valve, the amount of refrigerant in the freezer compartment cooler during defrosting can be reduced to an extremely small amount, and wasteful heating of the refrigerant by the defrosting means can be greatly reduced. Since it is possible to reduce the amount of power consumption of the defrosting means can be reduced from the conventional, it is extremely energy saving, and the calorific value of the defrosting means can be reduced to a calorific value below the ignition temperature of the flammable refrigerant,
Since there is almost no refrigerant in the freezer compartment cooler when the freezer compartment cooler is heated during defrosting, in an environment where the flammable refrigerant leaks into the installation atmosphere of the defrosting means while maintaining the defrosting ability at or above the conventional level Even if defrosting is performed, the possibility of ignition of the combustible refrigerant can be greatly reduced.

Further, according to the present invention, when the defrosting of the refrigerating cooler is performed, the switching valve is controlled so that the refrigerant does not flow to both the refrigerating compartment cooler and the refrigerating compartment cooler. After the compressor is operated for 20 to 90 seconds, the defrosting means is operated. Therefore, the amount of frost to be defrosted by the defrosting means is reduced by reducing the amount of frost on the freezer compartment cooler, and the check valve By closing the switching valve and operating the compressor before defrosting in addition to controlling the switching valve, the amount of refrigerant in the freezer compartment cooler during defrosting can be reduced to an extremely small amount, and wasteful heating of the refrigerant by the defrosting means can be greatly reduced. Since the power consumption of the defrosting means is extremely energy-saving, the calorific value of the defrosting means can be reduced to a heat value lower than the ignition temperature of the flammable refrigerant. There is almost no refrigerant in the freezer compartment cooler when the cooler is heated. Ability to be greatly reduced the likelihood of ignition of the flammable refrigerant even when the defrosting in an environment that leaks were made to the installation is flammable refrigerant defrosting means while maintaining the conventional equivalent or more.

Further, since the operation of the compressor is performed for 20 seconds to 90 seconds, useless operation in which the capacity of the compressor exceeds the upper limit can be prevented, and at the same time, the reliability of the compressor due to an excessive decrease in pressure can be prevented. .

The invention described in claim 5 is the same as the claim 2
In addition to the invention according to any one of claims 4 to 7, the switching valve is opened so that the condenser and the freezer compartment cooler are communicated before the defrosting means stops. The reduction of the amount of frost reduces the amount of frost to be defrosted by the defrosting means. In addition to the control of the check valve and the switching valve, the closing of the switching valve before defrosting and the operation of the compressor cause the Since the amount of the refrigerant in the freezer compartment cooler is extremely small, wasteful heating of the refrigerant by the defrosting means 26 can be greatly reduced, and even if the refrigerant leaks due to the heating of the defrost, the ignition concentration is not reached.

[0304] From this, the power consumption of the defrosting means can be reduced conventionally, which is extremely energy saving, and the calorific value of the defrosting means can be reduced to a heat value lower than the ignition temperature of the combustible refrigerant. Even if the flammable refrigerant is defrosted in an environment where the flammable refrigerant has leaked into the installation atmosphere of the defrosting means while maintaining the same or higher performance, the possibility of ignition of the flammable refrigerant can be greatly reduced.

Further, since the compressor can be smoothly started after the completion of the defrosting, the temperature rise of the freezing compartment accompanying the heating of the defrosting means at the time of defrosting can be rapidly cooled. Deterioration of stored food due to temperature rise can be prevented.

The invention described in claim 6 is the first invention.
In addition to the invention according to any one of claims 1 to 3, the switching valve is opened so that the condenser and the refrigerator cooler are communicated during the operation of the defrosting means. The amount of frost to be defrosted by the defrosting means is reduced by the reduction of the amount of frost, and in addition to the control of the check valve and the switching valve, the switching valve is closed and the compressor is operated before defrosting, so that freezing during defrosting is performed. By reducing the amount of refrigerant in the room cooler to a very small amount, wasteful heating of the refrigerant by the defrosting means can be greatly reduced. Since the amount of heat can be reduced to a heat value that is lower than the ignition temperature of the flammable refrigerant, defrosting is performed in an environment where the flammable refrigerant leaks to the installation atmosphere of the defrost means while maintaining the defrosting ability at or above the conventional level. Can greatly reduce the possibility of ignition of flammable refrigerants

Further, since the compressor can be smoothly started after the completion of the defrosting, the temperature rise of the freezing room due to the heating of the defrosting means at the time of defrosting can be rapidly cooled. Deterioration of stored food due to temperature rise can be prevented.

The invention described in claim 7 is the same as the invention in claim 6
In addition to the invention described in the above, since the compressor is operated during the operation of the defrosting means, the amount of frost to be defrosted by the defrosting means is reduced by reducing the amount of frost formed in the freezer compartment cooler, and the check By closing the switching valve and operating the compressor before defrosting in addition to controlling the valve and the switching valve, the amount of refrigerant in the freezer compartment cooler during defrosting is reduced to an extremely small amount, and unnecessary refrigerant heating by the defrosting means is performed. Since it can be greatly reduced, the amount of power consumption of the defrosting means can be reduced from the conventional one and it is extremely energy saving, and the calorific value of the defrosting means can be reduced to the calorific value below the ignition temperature of the flammable refrigerant,
It is possible to greatly reduce the possibility of ignition of the flammable refrigerant even when defrosting is performed in an environment where the flammable refrigerant has leaked into the installation atmosphere of the defrosting means while maintaining the defrosting ability at or above the conventional level. In addition, since the compressor can be smoothly started after the completion of defrosting, the temperature rise of the freezing compartment 2 due to the heating of the defrosting means at the time of defrosting can be quickly cooled. Deterioration of stored food due to temperature rise can be prevented.

Furthermore, since the refrigerator compartment is sufficiently cooled when the refrigerator compartment is cooled after defrosting, it is possible to prevent food deterioration due to insufficient cooling of the refrigerator compartment due to the cooling of the refrigerator compartment.

[0310] The invention according to claim 8 provides a refrigeration cycle in which a compressor, a condenser, a decompression mechanism, and an evaporator are connected, and a refrigeration cycle below the ignition temperature of a combustible refrigerant for defrosting the evaporator. Since the refrigeration cycle uses a flammable refrigerant, the flammable refrigerant heated together with the evaporator during the defrosting of the evaporator has a higher thermal conductivity than the conventional HCF refrigerant. It is possible to lower the temperature by lowering the calorific value of the frost means, and even if the flammable refrigerant in the refrigeration cycle leaks into the refrigerator, even if defrosting is performed, the defrost means is Since the temperature is lower than the ignition temperature of the flammable refrigerant, the risk of ignition is reduced.

[0311] The invention according to claim 9 provides the invention according to claim 8
In addition to the invention described in the above, the defrosting means is a first glass tube,
A second glass tube located inside the first glass tube and having an outer diameter smaller than the inner diameter of the first glass tube; and a metal resistor disposed between the first glass tube and the second glass tube. The first glass tube and the second glass even if the flammable refrigerant leaks if the heater wire rises above the ignition temperature of the flammable refrigerant for some reason. Since the space volume around the heater wire surrounded by the pipe is small,
As the amount of flammable refrigerant flowing around the heater wire is small and the amount of air containing oxygen necessary for the flammable refrigerant to burn is small, it does not ignite, ensuring a defrosting capacity equal to or higher than that of the conventional type Meanwhile, the heater wire can be set to a temperature lower than the ignition temperature of the flammable refrigerant, and the risk of ignition can be reduced even if defrosting is performed when the flammable refrigerant leaks into the atmosphere of the defrosting means.

[0312] According to a tenth aspect of the present invention, in addition to the eighth aspect, the defrosting means includes a glass tube, and a heater wire made of a metal resistor is installed inside the glass tube. Since the glass beads are filled, even if the flammable refrigerant leaks if the heater wire rises above the ignition temperature of the flammable refrigerant for some reason, the space volume around the heater wire in the glass tube will be extremely large. Since it is small, the amount of flammable refrigerant flowing into the glass tube and coming into contact with the heater wire is extremely small, and the amount of air containing oxygen necessary for combustion of the flammable refrigerant does not ignite. While ensuring the above defrosting ability, the heater wire can be set to a temperature lower than the ignition temperature of the flammable refrigerant, and the risk of ignition even if defrosting is performed when the flammable refrigerant leaks into the atmosphere of the defrosting means 26. Lower Kill.

[0313] According to the invention of claim 11, in addition to the invention of claim 10, since the glass beads are transparent, the glass beads are not only excellent in heat conduction but also transparent. Since the heat rays from the heater wires are transmitted through the heater wires, heat radiation from the heater wires to the outside is promoted, and the temperature is further reduced.

Further, even if the heater wire rises above the ignition temperature of the flammable refrigerant for some reason, even if the flammable refrigerant leaks, the space volume around the heater wire in the glass tube is very small. Since the amount of the flammable refrigerant flowing into the glass tube and coming into contact with the heater wire is extremely small, the flammable refrigerant does not ignite because the amount of air containing oxygen required for combustion is small.

[0315] From this, it is possible to set the heater wire to a temperature lower than the ignition temperature of the flammable refrigerant while securing the defrosting ability equal to or higher than the conventional one, and to perform defrosting when the flammable refrigerant leaks into the atmosphere of the defrosting means. Even if performed, the possibility of ignition can be reduced.

[0316] In addition to the invention described in the tenth aspect, the invention according to the twelfth aspect is characterized in that the glass beads filled in the glass tube have a filling amount of less than 100%. The inside is air, and the glass beads have very good thermal conductivity to air, so the heat conduction from the heater wire to the glass tube is very good, and the heat generation is the same and heat dissipation is promoted. The temperature of the heater wire decreases. Therefore, even if the heater wire rises above the ignition temperature of the flammable refrigerant for any reason, even if the flammable refrigerant leaks, the space volume around the heater wire in the glass tube is very small, Since the amount of the flammable refrigerant flowing into contact with the heater wire is extremely small, the flammable refrigerant does not ignite due to the small amount of oxygen-containing air required for combustion.

Further, the heater wire thermally expands as the temperature rises. At this time, the expansion is smoothly absorbed by the gap.

From this, it is possible to set the heater wire to a temperature lower than the ignition temperature of the flammable refrigerant while securing the defrosting ability equal to or higher than the conventional one, and to perform defrosting when the flammable refrigerant leaks into the atmosphere of the defrosting means. Even if performed, the possibility of ignition can be reduced.

In addition, defects such as disconnection due to suppression of thermal expansion of the heater wire can be prevented, and long-term reliability can be ensured.

The thirteenth aspect of the present invention is the defrosting means according to the tenth aspect, in which both ends of the glass tube are sealed, so that heat dissipation is promoted by glass beads having good heat conductivity. Temperature and the volume of space inside the glass tube reduce the temperature of the heater wire to a temperature lower than the ignition temperature of the flammable refrigerant while ensuring the same or higher defrosting capacity as before, and the flammable refrigerant leaks into the atmosphere of the defrosting means Even if defrosting is performed, the possibility of ignition can be reduced.

In addition, the amount of water in the glass tube can be extremely reduced, defects such as disconnection due to corrosion of the heater wire can be prevented, and long-term reliability can be ensured.

[0324] According to the fourteenth aspect of the present invention, in addition to the tenth aspect, a defrosting means cooling fan for cooling the defrosting means is installed near the defrosting means. In addition to lowering the temperature, since the defrosting ability is improved, the calorific value can be reduced and the temperature can be further reduced,
The heater wire can be set to a temperature lower than the ignition temperature of the flammable refrigerant while ensuring the same or higher defrosting capacity as before, and even if the flammable refrigerant leaks into the atmosphere of the defrost means, ignition is possible even if defrosting is performed Sex can be lower.

According to a fifteenth aspect of the present invention, in addition to the eighth aspect, the defrosting means comprises a glass tube and a heater wire made of a metal resistor inside the glass tube. Since the surface of the glass tube is coated with a radiation-promoting material that promotes radiation, the heater wire can be set to a temperature lower than the ignition temperature of the flammable refrigerant while maintaining the same or higher defrosting capacity as before, and the flammable refrigerant is removed. Even if defrosting is performed when the gas leaks into the atmosphere of the frost means, the possibility of ignition can be reduced.

Furthermore, since it is only necessary to coat the surface of the glass tube with the radiation promoting material, the production is simple and inexpensive.

[0325] Further, in the invention of claim 16, in addition to the invention of claim 15, since the radiation promoting material is transparent, the radiation promoting material is transparent in addition to promoting the radiation heat radiation of the radiation promoting material. Since the amount of transmitted radiant heat rays increases, the temperature of the heater wire decreases, and the heater wire can be set to a temperature lower than the ignition temperature of the flammable refrigerant while securing the defrosting ability equal to or higher than the conventional one. Even if defrosting is performed when the gas leaks into the atmosphere of the defrosting means, the possibility of ignition can be reduced, and the production is simple and inexpensive.

According to a seventeenth aspect of the present invention, in addition to the eighth aspect, the defrosting means includes a glass tube, a heater wire made of a metal resistor inside the glass tube, and a surface of the glass tube. And a roof for preventing direct contact of the defrost water with the roof, and since the width of the roof is smaller than the width of the evaporator, convection inhibition from the defrost means to the evaporator can be prevented, Since it is possible to prevent air path obstruction at the time of cooling, the heater wire can be set to a temperature lower than the ignition temperature of the flammable refrigerant while securing the defrosting ability equal to or higher than the conventional case, and the flammable refrigerant leaks to the atmosphere of the defrost means. Even if defrosting is performed, the possibility of ignition can be reduced.

In addition, deterioration of stored food due to insufficient cooling at the time of cooling can be prevented.

[0328] The invention according to claim 18 is the invention according to claim 8, wherein the defrosting means includes a metal pipe, a heater wire made of a metal resistor provided inside the metal pipe, and a heater. It is composed of an insulating material for insulating the wire and the metal pipe, and is in contact with the evaporator, and a water pan with heating means with heating means is installed below the evaporator, so that defrosting is performed. The means, in addition to the temperature drop,
Since the defrosting capacity is improved, the calorific value can be reduced and the temperature can be further lowered, so that the heater wire is kept at a temperature lower than the ignition temperature of the flammable refrigerant while saving energy and at the same time maintaining the same or higher defrosting capacity as before. When the flammable refrigerant leaks into the atmosphere of the defrosting means, the possibility of ignition can be further reduced even if the defrosting is performed.

In addition, the evaporator that has fallen into the water pan with the heating means and the defrosted water around the evaporator can be smoothly discharged to the outside. Since it is possible to prevent the ventilation resistance of the vessel from increasing and insufficient cooling, it is possible to prevent the food from deteriorating.

According to a nineteenth aspect of the present invention, in addition to the eighth aspect, the defrosting means comprises a glass tube and a heater wire made of a metal resistor inside the glass tube. Since the auxiliary heater is provided above the evaporator, the auxiliary heater is in contact with the evaporator, so that the defrosting efficiency is good and the melting point of frost is 0 during defrosting.
Since the temperature is low near ℃, the temperature can be reduced to a temperature lower than the ignition temperature of the flammable refrigerant while maintaining the same defrosting capacity as before, and if the flammable refrigerant leaks into the atmosphere of the defrosting means, defrosting will occur. Even if done, the risk of ignition can be reduced,
The defrosting means is inexpensive because it only has to reduce the calorific value using a defrosting tube equivalent to the conventional one.

[0331] The twentieth aspect of the present invention provides a refrigeration cycle in which a compressor, a condenser, a decompression mechanism, and an evaporator are functionally connected in an annular manner, and a compressor separate from a pipe constituting the refrigeration cycle. It has a bypass pipe that directly pipes the evaporator,
The bypass pipe is provided with a valve in the path, and the flammable refrigerant is sealed in the refrigerant, so defrosting at a very low temperature can be performed compared to the conventional high-temperature defrosting tube heater. In a refrigerator or the like using a refrigerant, the possibility of ignition can be extremely reduced even if defrosting is performed when the flammable refrigerant leaks into the refrigerator.

Furthermore, since heat is efficiently transferred to frost in contact with the evaporator to perform heat defrosting, defrosting can be performed very efficiently and the defrosting time can be extremely reduced. Since the operation is continuously performed during the defrosting, there is no rush current due to the activation of the compressor as in the case of the normal defrosting, thereby saving energy.

According to a twenty-first aspect of the present invention, in addition to the twentieth aspect, the valve has an opening / closing function, and when the valve is open, the inner diameter of the flow path is the minimum inner diameter of the high-pressure pipe. Since the size of the heater is equal to or larger than that of the conventional heater, it is possible to perform defrosting at a very low temperature compared to a conventional high-temperature defrosting tube heater. The possibility of ignition can be extremely reduced even if defrosting is performed when leakage occurs.

Further, since there is no obstruction of circulation of the hot gas refrigerant by the valve, heat is efficiently transferred to frost in contact with the evaporator to perform heating defrosting, so that defrosting is performed very efficiently. Since the frost time can be extremely shortened, and since the compressor operates continuously during defrosting, there is no rush current due to the activation of the compressor as in normal defrosting, so that it is very energy saving.

[0335] Further, in accordance with the present invention, in addition to the twentieth aspect, the evaporator inlet pipe, which is a pipe from the bypass pipe to the evaporator, is located near the upstream side of the ventilation air for heat exchange. Because the evaporator outlet piping from the evaporator to the compressor suction is located near the downstream side of the ventilation air that exchanges heat with the evaporator, it is very much compared to such a high temperature defrost pipe heater. Since low-temperature defrosting can be performed, in a refrigerator or the like using a combustible refrigerant, the risk of ignition can be extremely reduced even if the defrosting is performed when the combustible refrigerant leaks into the refrigerator.

Further, since the evaporator can be made uniform and the heat defrosting is performed by efficiently transferring heat to the frost in contact with the evaporator, the defrosting is performed very efficiently and the defrosting time is extremely short. , And the compressor operates continuously during defrosting, so that there is no inrush current due to the activation of the compressor as in normal defrosting.

[0337] The invention according to claim 23 is, in addition to the invention according to claim 20, a water tray with heating means provided with a built-in heating means and provided with a drain port for discharging defrost water to the outside of the refrigerator. Since defrosting at a very low temperature can be performed as compared with such a high-temperature defrosting tube heater, in a refrigerator or the like using a flammable refrigerant, the flammable refrigerant leaked into the refrigerator. In this case, even if defrosting is performed, the possibility of ignition can be extremely reduced.

Furthermore, since heat is efficiently transferred to the frost in contact with the evaporator to perform heating defrosting, the defrosting can be performed very efficiently and the defrosting time can be extremely reduced. Since it operates continuously during defrosting, there is no rush current due to the start of the compressor as in normal defrosting, so that it is very energy saving.

In addition, since the cooling speed at the time of cooling after defrosting is increased, deterioration of food due to temperature rise after defrosting can be prevented.

The invention according to claim 24 is characterized in that, in addition to the invention described in claim 20, the evaporator outlet pipe from the evaporator to the compressor is provided with a heating means, so that the conventional high temperature Defrosting can be performed at a very low temperature compared to the defrosting tube heater, so if a flammable refrigerant leaks into the refrigerator, etc. Can be extremely reduced.

Furthermore, since heat is efficiently transferred to frost in contact with the evaporator to perform heat defrosting, the defrosting can be performed very efficiently and the defrosting time can be extremely reduced. Since it operates continuously during defrosting, there is no rush current due to the start of the compressor as in normal defrosting, so that it is very energy saving.

In addition, breakage of the compressor due to liquid back during defrosting can be prevented, and a long life can be ensured.

In addition, in the invention according to claim 25, in addition to the invention according to claim 20, since the valve has a throttle function, it is very much compared with a conventional high-temperature defrosting tube heater. Since low-temperature defrosting can be performed, in a refrigerator or the like using a flammable refrigerant, the possibility of ignition can be extremely reduced even if defrosting is performed when the flammable refrigerant leaks into the refrigerator.

Further, since heat is efficiently transferred to frost in contact with the evaporator to perform heat defrosting, very efficient defrosting is performed, and heat is efficiently transferred to perform heat defrosting. Since the defrosting is performed efficiently and the defrosting time can be extremely reduced, and the compressor operates continuously during defrosting, there is no rush current due to the start of the compressor as in normal defrosting Therefore, it is very energy saving.

In addition, since the refrigerant is circulated by an amount corresponding to the formation of frost on the evaporator, unnecessary heating of the evaporator is reduced, the temperature rise in the refrigerator is reduced, and the cooling speed during cooling is increased. Food deterioration can be prevented.

According to a twenty-sixth aspect of the present invention, in addition to the twenty-seventh aspect, an evaporator outlet temperature detecting means for detecting a temperature is provided in the evaporator outlet pipe, and the evaporator outlet temperature detecting means is provided. Since the throttle of the valve is controlled, defrosting at a very low temperature can be performed as compared with a conventional high-temperature defrosting tube heater, so that a combustible refrigerant is stored in a refrigerator or the like using a combustible refrigerant. Even if defrosting is performed when leaked into the inside, the possibility of ignition can be extremely reduced.

Further, since heat is efficiently transferred to frost in contact with the evaporator to perform heat defrosting, very efficient defrosting is performed and heat is efficiently transferred to perform heat defrosting. Since the defrosting is performed efficiently and the defrosting time can be extremely reduced, and the compressor operates continuously during defrosting, there is no rush current due to the start of the compressor as in normal defrosting Therefore, it is very energy saving.

In addition, damage due to liquid back of the compressor during defrosting can be prevented, and a long life can be ensured.

According to a twenty-seventh aspect of the present invention, in addition to the twentieth aspect, since the compressor can change the rotation speed, the defrosting tube heater having a high temperature as in the prior art can be obtained. Since defrosting at a very low temperature can be performed compared to, in a refrigerator or the like using a flammable refrigerant, the possibility of ignition is extremely low even if defrosting is performed when the flammable refrigerant leaks into the refrigerator. it can.

Further, since heat is efficiently transferred to frost in contact with the evaporator to perform heat defrosting, very efficient defrosting is performed, and heat is efficiently transferred to perform heat defrosting. Since the defrosting is performed efficiently and the defrosting time can be extremely reduced, and the compressor operates continuously during defrosting, there is no rush current due to the start of the compressor as in normal defrosting Therefore, it is very energy saving.

In addition, it is possible to prevent damage due to liquid back of the compressor at the time of defrosting, to secure a long life, and to prevent liquid back by changing the rotation speed of the compressor, thereby saving energy.

[Brief description of the drawings]

FIG. 1 is a refrigeration system diagram of a refrigerator according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a main part of the refrigerator according to the first embodiment of the present invention.

FIG. 3 is a time chart of the refrigerator according to the second embodiment of the present invention.

FIG. 4 is a time chart of the refrigerator according to the third embodiment of the present invention.

FIG. 5 is a time chart of a refrigerator according to a fourth embodiment of the present invention.

FIG. 6 is a time chart of the refrigerator according to the fifth embodiment of the present invention.

FIG. 7 is a time chart of the refrigerator according to the sixth embodiment of the present invention.

FIG. 8 is a time chart of the refrigerator in the seventh embodiment of the present invention.

FIG. 9 is a refrigeration system diagram of a refrigerator according to an eighth embodiment of the present invention.

FIG. 10 is a sectional view of a defrosting means of a refrigerator in a ninth embodiment of the present invention.

FIG. 11 is a sectional view of the defrosting means of the refrigerator in the tenth, eleventh, and thirteenth embodiments of the present invention.

FIG. 12 is a sectional view of a defrosting means of a refrigerator according to a twelfth embodiment of the present invention.

FIG. 13 is a sectional view of a main part of a refrigerator in a fourteenth embodiment of the present invention.

FIG. 14 is a sectional view of the defrosting means of the refrigerator in the fifteenth and sixteenth embodiments of the present invention.

FIG. 15 is a sectional view of a main part of a refrigerator in a seventeenth embodiment of the present invention.

FIG. 16 is a sectional view of a defrosting means of a refrigerator in a seventeenth embodiment of the present invention.

FIG. 17 is a sectional view of a main part of a refrigerator according to an eighteenth embodiment of the present invention.

FIG. 18 is a sectional view of the defrosting means of the refrigerator in the eighteenth embodiment of the present invention.

FIG. 19 is a sectional view of a main part of a refrigerator in a nineteenth embodiment of the present invention.

FIG. 20 is a diagram showing a refrigeration system of a refrigerator according to Embodiments 20 and 21 of the present invention.

FIG. 21 is a refrigeration system diagram of a refrigerator according to a twenty-second embodiment of the present invention.

FIG. 22 is a sectional view of a main part of a refrigerator in a twenty-third embodiment of the present invention.

FIG. 23 is a refrigeration system diagram of a refrigerator according to a twenty-fourth embodiment of the present invention.

FIG. 24 is a characteristic diagram of a throttle amount of a valve of a refrigerator in a twenty-fifth embodiment of the present invention.

FIG. 25 is a refrigeration system diagram of a refrigerator in a twenty-sixth embodiment of the present invention.

FIG. 26 is a refrigeration system diagram of a refrigerator according to a twenty-seventh embodiment of the present invention.

FIG. 27 is a longitudinal sectional view of a main part of a conventional refrigerator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Refrigerator main body 2 Freezer room 3 Refrigerator room 10 Evaporator 14 Drainage port 16 Roof 18 Compressor 19 Condenser 20 Switching valve 21 Low evaporation temperature decompression mechanism 22 High evaporation temperature decompression mechanism 23 Refrigerator cooler 24 Freezer Cooler 25 Check valve 26 Defrosting means 34 Decompression device 35 First glass tube 36 Second glass tube 37 Heater wire 42 Glass tube 43 Glass beads 45 Defrosting means cooling fan 46 Radiation promoting material 48 Metal pipe 49 Insulating material Reference Signs List 50 water receiving pan with heating means 51 auxiliary heater 52 bypass pipe 53 valve 54 evaporator inlet pipe 55 evaporator outlet pipe 56 heating means 57 evaporator outlet temperature detecting means

Continuation of the front page (72) Inventor Koichi Nishimura 4-5-2-5 Takaidahondori, Higashiosaka-shi, Osaka Matsushita Refrigeration Co., Ltd. F-term (reference) 3L045 AA03 BA01 BA03 CA02 CA03 DA02 EA01 GA04 HA02 HA06 JA01 JA15 JA16 LA05 LA14 MA04 NA17 PA01 PA04 PA05 3L046 AA03 BA04 CA07 GA01 JA03 JA05 JA14 KA04 MA01 MA04 MA05

Claims (27)

[Claims] A refrigerator having a freezer compartment and a refrigerating compartment provided independently so as to prevent convection of air;
Refrigerator compartment cooler with high evaporation temperature for refrigeration, high evaporation temperature decompression mechanism with small decompression for high evaporation temperature, refrigeration with low evaporation temperature for refrigeration connected in parallel with refrigerator compartment cooler A cooling device for the room, a pressure-reducing mechanism for the low evaporation temperature having a large reduced pressure for the low evaporation temperature, a switching valve for controlling the refrigerant not to flow simultaneously to the cooling device for the refrigerator and the cooling device for the freezing room,
A refrigeration system in which a check valve for preventing the backflow of the refrigerant is functionally connected to the outlet of the refrigerator for the freezer compartment, and a refrigeration system in which the flammable refrigerant is sealed, and a defrosting means for defrosting the refrigerator for the freezer compartment. Equipped refrigerator. 2. The refrigerator according to claim 1, wherein the switching valve is controlled so that the refrigerant does not flow into the freezer compartment cooler when the freezer compartment cooler is defrosted. 3. When defrosting the freezer compartment cooler, the switching valve is controlled so that the refrigerant does not flow into both the refrigerator compartment cooler and the freezer compartment cooler, and the compressor is operated for an arbitrary time. The refrigerator according to claim 1, wherein the defrosting means is operated after the operation. 4. When defrosting the freezer compartment cooler, the switching valve is controlled so that the refrigerant does not flow into both the refrigerator compartment cooler and the freezer compartment cooler, and the compressor is operated from 20 seconds to 90 seconds. The refrigerator according to claim 3, wherein the defrosting means is operated after the operation for two seconds. 5. The switching valve is opened so that the condenser and the refrigerator cooler are communicated with each other before the defrosting means stops.
The refrigerator according to any one of claims 1 to 4. 6. The refrigerator according to claim 1, wherein the switching valve is opened so that the condenser and the refrigerator cooler communicate with each other during the operation of the defrosting means. 7. The refrigerator according to claim 6, wherein the compressor is operated while the defrosting means is operating. 8. A refrigeration cycle comprising a compressor, a condenser, a decompression mechanism, and an evaporator connected to each other; A refrigerator that uses a flammable refrigerant for the cycle. 9. A defrosting means comprising: a first glass tube;
A second glass tube located inside the glass tube and having an outer diameter smaller than the inner diameter of the first glass tube; and a first glass tube and a second glass tube.
9. The refrigerator according to claim 8, comprising a heater wire made of a metal resistor disposed between the glass tubes. 10. The refrigerator according to claim 8, wherein the defrosting means is provided with a glass tube, and a heater wire made of a metal resistor is installed inside the glass tube and filled with glass beads. 11. The glass beads are transparent.
A refrigerator according to claim 1. 12. The refrigerator according to claim 10, wherein the content of the glass beads filled in the glass tube is less than 100%. 13. The refrigerator according to claim 10, wherein both ends of the glass tube are sealed. 14. The refrigerator according to claim 8, further comprising a defrosting means cooling fan for cooling the defrosting means near the defrosting means. 15. A defrosting means comprising a glass tube and a heater wire made of a metal resistor inside the glass tube, wherein the surface of the glass tube is coated with a radiation promoting material for promoting radiation. Item 10. The refrigerator according to Item 8. 16. The radiation enhancing material is transparent.
A refrigerator according to claim 1. 17. The defrosting means comprises a glass tube, a heater wire made of a metal resistor inside the glass tube, and a roof for preventing defrost water from directly contacting the surface of the glass tube. The refrigerator according to claim 8, wherein the width of the roof is smaller than the width of the evaporator. 18. A defrosting means includes: a metal pipe; a heater wire made of a metal resistor installed inside the metal pipe;
It is composed of an insulating material for insulating the heater wire and the metal pipe, and is in contact with an evaporator,
9. The refrigerator according to claim 8, wherein a water pan with heating means having heating means is provided below the evaporator. 19. The apparatus according to claim 8, wherein the defrosting means comprises a glass tube and a heater wire made of a metal resistor inside the glass tube, and an auxiliary heater is provided above the evaporator. The refrigerator as described. 20. A refrigeration cycle in which a compressor, a condenser, a decompression mechanism, and an evaporator are functionally connected in a ring shape, and the compressor and the evaporator are directly piped separately from pipes forming the refrigeration cycle. A refrigerator having a bypass pipe, a valve in a path of the bypass pipe, and a refrigerant filled with a flammable refrigerant. 21. The refrigerator according to claim 20, wherein the valve has an opening / closing function, and when the valve is opened, the inner diameter of the flow path is equal to or greater than the minimum inner diameter of the high-pressure pipe. 22. An evaporator inlet pipe, which is a pipe from the bypass pipe to the evaporator, is located near the upstream side of the ventilation air for heat exchange, and the evaporator outlet pipe from the evaporator to the suction of the compressor is the evaporator outlet pipe. The refrigerator according to claim 20, wherein the refrigerator is located near the downstream side of the ventilation air that exchanges heat with the vessel. 23. The refrigerator according to claim 20, further comprising a water tray provided with heating means, the heating means being provided with a water outlet for discharging defrost water to the outside of the refrigerator. 24. The refrigerator according to claim 20, wherein an evaporator outlet pipe from the evaporator to the compressor is provided with heating means. 25. The refrigerator according to claim 20, wherein the valve has a throttle function. 26. The refrigerator according to claim 25, wherein an evaporator outlet temperature detecting means for detecting a temperature is provided in the evaporator outlet pipe, and the throttle of the valve is controlled by the evaporator outlet temperature detecting means. 27. The refrigerator according to claim 20, wherein the number of rotations of the compressor is variable.